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[87]	3	<meta http-equiv="CONTENT-TYPE" content="text/html; charset=windows-1252"><title>PALM chapter 3.5.5</title> <meta name="GENERATOR" content="StarOffice 7 (Win32)"> <meta name="AUTHOR" content="Siegfried Raasch"> <meta name="CREATED" content="20040802;14050943"> <meta name="CHANGED" content="20041117;12180008"> <meta name="KEYWORDS" content="parallel LES model"> <style>
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	8	<body style="direction: ltr;" lang="en-US"><h3 style="line-height: 100%;"><font size="4">3.5.4
	9	User-defined output quantities<br>
	10	</font></h3>A very typical request of users is the
	11	calculation and
[5]	12	output of
	13	quantities which are not part of PALM's standard output. The basic user
	14	interface includes a number of subroutines which allow the calculation
[87]	15	of user-defined quantities and output of these quantities as time series, (horizontally averaged) vertical profile, 2d cross
[62]	16	section or 3d volume data. The respective subroutines
[87]	17	contain sample code lines (written as comment lines) for defining, calculating and
[89]	18	output of such quantities.<br><br>Output times, averaging intervals, etc. are steered by the same variables as used for the standard PALM output quantities, e.g. <a href="chapter_4.2.html#dt_data_output">dt_data_output</a>.<br><br>The
[87]	19	rest of this chapter explains step-by-step how to modify/extend the
[89]	20	default file user_interface.f90 in order to generate the respective output.<br><br><br><h4>Output of vertical profiles</h4>This example shows the output of the
	21	quantity "turbulent resolved-scale horizontal momentum flux" (uv). If more than one user-defined
	22	quantity shall be output, the following steps have to be carried out in the
	23	same way for each of the quantities.<br><br><ol><li>The
	24	quantity has to be given a unique string identifier, e.g. <span style="font-style: italic;">'uv'</span>.
	25	This identifier must be different from the identifiers used for the
	26	PALM standard output (see list in description of parameter <a href="chapter_4.2.html#data_output_pr">data_output_pr</a>).
	27	To switch on output of this quantity, the user has to assign the string
	28	identifier to the parameter <a href="chapter_4.3.html#data_output_pr_user">data_output_pr_user</a>,
	29	eg.:<br><br><span style="font-family: monospace;">
	30	data_output_pr_user</span> = <span style="font-style: italic;">'uv'</span>,<span style="font-style: italic;"></span><span style="font-style: italic;"></span><span style="font-style: italic;"></span><span style="font-style: italic;"></span><span style="font-style: italic;"></span><span style="font-style: italic;"></span><br><br></li><li>For
	31	the
	32	quantity, an identification number, a physical unit, and the vertical
	33	grid on which it is defined (u- or w-grid), has to be assigned (subroutine <a href="chapter_3.5.1.html#user_check_data_output_pr"><span style="font-family: monospace;">user_check_data_output_pr</span></a>):<span style="font-family: monospace;"><br><br>    CASE (
	34	'uv' )<br></span><span style="font-family: monospace;">       index = pr_palm + <span style="color: rgb(255, 0, 0);">1<span style="color: rgb(0, 0, 0);">
	35
	36
	37	! identification number</span></span><br>       dopr_index(var_count) = index<br>       dopr_unit(var_count)  = '<span style="color: rgb(255, 0, 0);">m2/s2</span>'
	38
	39	! physical unit<br>       hom(:,2,index,:)      = SPREAD( <span style="color: rgb(255, 0, 0);">zu</span>, 2, statistic_regions+1 )    ! vertical grid<br></span><br>Here only the those parts in <span style="color: rgb(255, 0, 0);">red</span> color have to be given by the user appropriately.<br>The identification number (<span style="font-family: Courier New,Courier,monospace;">index</span>) must be within the range [<span style="font-family: Courier New,Courier,monospace;"> pr_palm+1 , pr_palm+max_pr_user</span> ], where <span style="font-family: Courier New,Courier,monospace;">max_pr_user</span> is the number of user-defined profiles as given by parameter <a href="chapter_4.3.html#data_output_pr_user">data_output_pr_user</a> in the respective PALM run. The physical unit has to be given with respect to the NetCDF conventions. If no unit is given,
	40	PALM will abort. The vertical grid has to be either <span style="font-family: Courier New,Courier,monospace;">zu</span> (u-grid) or <span style="font-family: Courier New,Courier,monospace;">zw</span> (w-grid).<br><br></li><li>The quantity has to be calculated for all gridpoints (subroutine <a href="chapter_3.5.1.html#user_statistics">user_statistics</a>):<br><br><span style="font-family: monospace;">    !$OMP DO</span><br style="font-family: monospace;"><span style="font-family: monospace;">    DO  i = nxl, nxr</span><br style="font-family: monospace;"><span style="font-family: monospace;">       DO  j = nys, nyn</span><br style="font-family: monospace;"><span style="font-family: monospace;">          DO  k = nzb_s_outer(j,i)+1, nzt</span><br style="font-family: monospace;"><span style="font-family: monospace;"></span><span style="font-family: monospace;"></span><span style="font-family: monospace;"></span><span style="font-family: monospace;">             sums_l(k,pr_palm+<span style="color: rgb(255, 0, 0);">1</span>,tn) = sums_l(k,pr_palm+<span style="color: rgb(255, 0, 0);">1</span>,tn) +           &</span><br style="font-family: monospace;"><span style="font-family: monospace;">                   <span style="color: rgb(255, 0, 0);">( 0.5 * ( u(k,j,i) + u(k,j,i+1) ) - hom(k,1,1,sr) ) * &</span></span><br style="font-family: monospace; color: rgb(255, 0, 0);"><span style="font-family: monospace; color: rgb(255, 0, 0);">
	41	( 0.5 * ( v(k,j,i) + v(k,j+1,i) ) - hom(k,1,2,sr) ) * &</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	42	* rmask(j,i,sr)<br>          ENDDO<br>       ENDDO<br>    ENDDO<br></span><br style="font-family: monospace;">Once again, only those parts in <span style="color: rgb(255, 0, 0);">red</span> have to be adjusted by the user.<br>The
	43	turbulent resolved-scale momentum flux uv is defined as the product
	44	of the deviations of the horizontal velocities from their respective
	45	horizontally averaged mean values. These mean values are stored in
	46	array <span style="font-family: Courier New,Courier,monospace;">hom(..,1,1,sr)</span> and <span style="font-family: Courier New,Courier,monospace;">hom(..,1,2,sr)</span> for the u- and v-component, respectively. Since due to the staggered grid, <span style="font-family: Courier New,Courier,monospace;">u</span> and <span style="font-family: Courier New,Courier,monospace;">v</span>
	47	are not defined at the same gridpoints, they have to be interpolated
	48	appropriately (here to the center of the gridbox). The result of the
	49	calculation is stored in array <span style="font-family: Courier New,Courier,monospace;">sums_l</span>.
	50	The second index of this array is the identification number of the
	51	profile which must match the one given in the previous step 2.</li></ol><br><h4>Output of timeseries</h4>still to be added<br> <br><h4><span style="font-weight: bold;">Output of 2d cross sections or 3d volume data</span></h4><br>This example shows the output of the
[87]	52	quantity "square of the u-component" (<span style="font-weight: bold;">Note:</span> this quantity
[5]	53	could of course easily be calculated from the u-component by
	54	postprocessing the PALM output so that calculation within PALM is not
[87]	55	necessarily required). If more than one user-defined
[89]	56	quantity shall be output, the following steps have to be carried out in the
[62]	57	same way for each of the quantities.<br><br><ol><li>The
	58	quantity has to be given a unique string identifier, e.g. <span style="font-style: italic;">'u2'</span>.
[5]	59	This identifier must be different from the identifiers used for the
[62]	60	PALM standard output (see list in description of parameter <a href="chapter_4.2.html#data_output">data_output</a>).
	61	To switch on output of this quantity, the user has to assign the string
	62	identifier to the parameter <a href="chapter_4.3.html#data_output_user">data_output_user</a>,
	63	eg.:<br><br><span style="font-family: monospace;">
	64	data_output_user</span> = <span style="font-style: italic;">'u2'</span>, <span style="font-style: italic;"> 'u2_xy_av'</span><br><br>The
	65	pure string <span style="font-style: italic;">'u2'</span>
[5]	66	switches on the output of instantaneous 3d volume data. Output of cross
	67	section data and time averaged data is switched on by additionally
[62]	68	appending the strings <span style="font-style: italic;">'_xy'</span>,
	69	<span style="font-style: italic;">'_xz'</span>, <span style="font-style: italic;">'_yz'</span>, and/or <span style="font-style: italic;">'_av'</span> (for a
	70	detailed explanation see parameter <a href="chapter_4.2.html#data_output">data_output</a>).<br><br></li><li>In
	71	order to store the quantities' grid point data within PALM, a 3d data
	72	array has to be declared in module <a href="chapter_3.5.1.html#user"><span style="font-family: monospace;">user</span></a>:<br><br><span style="font-family: monospace;">    REAL,
	73	DIMENSION(:,:,:), ALLOCATABLE ::  u2, u2_av</span><br><br>The
	74	second array <span style="font-family: monospace;">u2_av</span>
[5]	75	is needed in case that output of time averaged data is requested. It is
	76	used to store the sum of the data of the respective time levels over
[62]	77	which the average has to be carried out.<br><br><br></li><li>The
	78	data array has to be allocated in subroutine <a href="chapter_3.5.1.html#user_init"><span style="font-family: monospace;">user_init</span></a>:<br><br><span style="font-family: monospace;">
	79	ALLOCATE( u2(nzb:nzt+1,nys-1:nyn+1,nxl-1:nxr+1) )</span><br><br>In
[5]	80	case that output of time averaged data is requested, the array
	81	containing the sum has possibly to be read from the restart file (local
[62]	82	filename <a href="chapter_3.4.html#BININ">BININ</a>)
	83	by executing the following code in <span style="font-family: monospace;">user_init</span>:<br><br><span style="font-family: monospace;">
	84	IF ( initializing_actions == 'read_restart_data' )
	85	THEN</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	86	READ ( 13 )  field_chr</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	87	DO  WHILE ( TRIM( field_chr ) /= '*** end
	88	user ***' )</span><br style="font-family: monospace;"><br style="font-family: monospace;"><span style="font-family: monospace;">
	89	SELECT CASE ( TRIM( field_chr ) )</span><br style="font-family: monospace;"><br style="font-family: monospace;"><span style="font-family: monospace;">
	90	CASE ( 'u2_av' )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	91	ALLOCATE(
	92	u2_av(nzb:nzt+1,nys-1:nyn+1,nxl-1:nxr+1) )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	93	READ ( 13 )  u2_av</span><br style="font-family: monospace;"><br style="font-family: monospace;"><span style="font-family: monospace;">
	94	CASE DEFAULT</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	95	PRINT*,
	96	'+++ user_init: unknown
[5]	97	variable named "', &</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	98
[62]	99
	100	TRIM(
[5]	101	field_chr ), '" found in'</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	102	PRINT*,
	103	'
[62]	104	data from prior run on PE ', myid</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	105
	106	CALL local_stop</span><br style="font-family: monospace;"><br style="font-family: monospace;"><span style="font-family: monospace;">
	107	END SELECT<br>
	108	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	109	ENDIF</span><br style="font-family: monospace;"><br><br></li><li>The
	110	quantity has to be given a unit (subroutine <a href="chapter_3.5.1.html#user_check_data_output"><span style="font-family: monospace;">user_check_data_output</span></a>):<br><br><span style="font-family: monospace;">    CASE (
	111	'u2' )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	112	unit = 'm2/s2'</span><br> <br>Otherwise,
	113	PALM will abort.<br><br><br></li><li>The
[5]	114	vertical grid on which the quantity is defined (given by the levels
	115	'zu' or 'zw', on which the u- or w-component of the velocity are
[62]	116	defined) has to be specified for the NetCDF output files in subroutine <a href="chapter_3.5.1.html#user_define_netcdf_grid"><span style="font-family: monospace;">user_define_netcdf_grid</span></a>:<br><br><span style="font-family: monospace;">
	117	CASE ( 'u2', 'u2_xy', 'u2_xz', 'u2_yz' )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	118	grid = 'zu'</span><br> <br>As
	119	the example shows, this grid has to be defined for the 3d volume data
	120	as well as for all of the three cross sections.<br><span style="font-family: monospace;"><br><br></span></li><li>After
	121	each timestep, the quantity has to be calculated at all gridpoints and
	122	to be stored. This has to be done in subroutine <a href="chapter_3.5.1#user_actions"><span style="font-family: monospace;">user_actions</span></a>
	123	at location 'after_integration':<br><br><span style="font-family: monospace;">    CASE
	124	( 'after_integration' )</span><br style="font-family: monospace;"><span style="font-family: monospace;">!</span><br style="font-family: monospace;"><span style="font-family: monospace;">!--
	125	Enter actions to be done after every time integration (before</span><br style="font-family: monospace;"><span style="font-family: monospace;">!--
	126	data output)</span><br style="font-family: monospace;"><span style="font-family: monospace;">!--
	127	Sample for user-defined output:</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	128	DO  i = nxl-1, nxr+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	129	DO  j = nys-1, nyn+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	130	DO  k = nzb, nzt+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	131	u2(k,j,i) = u(k,j,i)**2</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	132	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	133	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	134	ENDDO</span><br><br> <br></li><li>In
[5]	135	case that output of time-averaged data is requested, the sum- and
	136	average-operations as well as the allocation of the sum-array have to
[62]	137	be carried out in subroutine <a href="chapter_3.5.1.html#user_3d_data_averaging"><span style="font-family: monospace;">user_3d_data_averaging</span></a>:<br><br><span style="font-family: monospace;">
	138	IF ( mode == 'allocate' )  THEN<br>
	139	...</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	140	CASE ( 'u2' )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	141	IF ( .NOT. ALLOCATED( u2_av ) )  THEN</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	142	ALLOCATE( u2_av(nzb:nzt+1,nys-1:nyn+1,nxl-1:nxr+1) )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	143	ENDIF</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	144	u2_av = 0.0<br>    ...</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	145	ELSEIF ( mode == 'sum' )  THEN<br>
	146	...</span><br style="font-family: monospace;"><span style="font-family: monospace;">       CASE
	147	( 'u2' )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	148	DO  i = nxl-1, nxr+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	149	DO  j = nys-1, nyn+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	150	DO  k = nzb, nzt+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	151	u2_av(k,j,i) = u2_av(k,j,i) + u2(k,j,i)</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	152	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	153	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	154	ENDDO<br>    ...</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	155	ELSEIF ( mode == 'average' )  THEN<br>
	156	...</span><br style="font-family: monospace;"><span style="font-family: monospace;">       CASE
	157	( 'u2' )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	158	DO  i = nxl-1, nxr+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	159	DO  j = nys-1, nyn+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	160	DO  k = nzb, nzt+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	161	u2_av(k,j,i) = u2_av(k,j,i) / REAL( average_count_3d )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	162	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	163	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	164	ENDDO</span><br><br> </li><li>For
	165	output of 2d cross sections, the gridpoint data of the quantity has to
	166	be resorted to array <span style="font-family: monospace;">local_pf</span>
	167	in subroutine <a href="chapter_3.5.1.html#user_data_output_2d"><span style="font-family: monospace;">user_data_output_2d</span></a>.
	168	Also the vertical grid, on which the quantity is defined, has to be set
	169	again:<br><br><span style="font-family: monospace;">    CASE
	170	( 'u2_xy', 'u2_xz', 'u2_yz' )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	171	IF ( av == 0 )  THEN</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	172	DO  i = nxl-1, nxr+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	173	DO  j = nys-1, nyn+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	174	DO  k = nzb, nzt+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	175	local_pf(i,j,k) = u2(k,j,i)</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	176	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	177	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	178	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	179	ELSE</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	180	DO  i = nxl-1, nxr+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	181	DO  j = nys-1, nyn+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	182	DO  k = nzb, nzt+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	183	local_pf(i,j,k) = u2_av(k,j,i)</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	184	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	185	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	186	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	187	ENDIF</span><br style="font-family: monospace;"><br style="font-family: monospace;"><span style="font-family: monospace;">
	188	grid = 'zu'</span><br> <br>The <span style="font-family: monospace;">ELSE</span> case is
	189	only needed in case that output of time-averaged data is requested.<br><br><br></li><li>For
	190	output of 3d volume data, the gridpoint data of the quantity has to be
	191	resorted to array <span style="font-family: monospace;">local_pf</span>
	192	in subroutine <a href="chapter_3.5.1.html#user_data_output_3d"><span style="font-family: monospace;">user_data_output_3d</span></a>.
	193	Also the vertical grid, on which the quantity is defined, has to be set
	194	again:<br><br><span style="font-family: monospace;">    CASE
	195	( 'u2' )</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	196	IF ( av == 0 )  THEN</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	197	DO  i = nxl-1, nxr+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	198	DO  j = nys-1, nyn+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	199	DO  k = nzb, nz_do</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	200	local_pf(i,j,k) = u2(k,j,i)</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	201	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	202	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	203	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	204	ELSE</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	205	DO  i = nxl-1, nxr+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	206	DO  j = nys-1, nyn+1</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	207	DO  k = nzb, nz_do</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	208	local_pf(i,j,k) = u2_av(k,j,i)</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	209	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	210	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	211	ENDDO</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	212	ENDIF</span><br style="font-family: monospace;"><br style="font-family: monospace;"><span style="font-family: monospace;">
	213	grid = 'zu'</span><br><br>The <span style="font-family: monospace;">ELSE</span> case is
	214	only needed in case that output of time-averaged data is requested.<br><br><br></li><li>In
	215	case of job chains, the sum array has to be written to the (binary)
	216	restart file (local filename <a href="chapter_3.4.html#BINOUT">BINOUT</a>)
	217	in subroutine <a href="chapter_3.5.1.html#user_last_actions"><span style="font-family: monospace;">user_last_actions</span></a>:<br><br><span style="font-family: monospace;">
	218	IF ( ALLOCATED( u2_av ) )  THEN</span><br style="font-family: monospace;"><span style="font-family: monospace;">
[5]	219	WRITE ( 14 )
	220	'u2_av
[62]	221	';  WRITE ( 14 )  u2_av</span><br style="font-family: monospace;"><span style="font-family: monospace;">
	222	ENDIF</span><br><br>Otherwise, the calculated
	223	time-average may be wrong.  </li></ol><hr>
	224	<p style="line-height: 100%;"><br><font color="#000080"><font color="#000080"><a href="chapter_3.5.3.html"><font color="#000080"><img src="left.gif" name="Grafik1" align="bottom" border="2" height="32" width="32"></font></a><a href="index.html"><font color="#000080"><img src="up.gif" name="Grafik2" align="bottom" border="2" height="32" width="32"></font></a><a href="chapter_3.5.5.html"><font color="#000080"><img style="border: 2px solid ; width: 32px; height: 32px;" alt="" src="right.gif" name="Grafik3"></font></a></font></font></p>
	225	<p style="line-height: 100%;"><i>Last
	226	change: </i> $Id: chapter_3.5.4.html 89 2007-05-25 12:08:31Z raasch $</p>
[5]	227	</body></html>

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