File: fftp_sample.F

package info (click to toggle)
ferret-vis 7.6.0-8
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 218,500 kB
  • sloc: fortran: 234,502; ansic: 51,843; csh: 2,516; makefile: 1,613; sh: 1,571; pascal: 569; sed: 184; lisp: 122; awk: 26
file content (448 lines) | stat: -rw-r--r-- 15,402 bytes parent folder | download | duplicates (6)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
*
* fftp_sample.F
*
*
*  This software was developed by the Thermal Modeling and Analysis
*  Project(TMAP) of the National Oceanographic and Atmospheric
*  Administration's (NOAA) Pacific Marine Environmental Lab(PMEL),
*  hereafter referred to as NOAA/PMEL/TMAP.
*
*  Access and use of this software shall impose the following
*  obligations and understandings on the user. The user is granted the
*  right, without any fee or cost, to use, copy, modify, alter, enhance
*  and distribute this software, and any derivative works thereof, and
*  its supporting documentation for any purpose whatsoever, provided
*  that this entire notice appears in all copies of the software,
*  derivative works and supporting documentation.  Further, the user
*  agrees to credit NOAA/PMEL/TMAP in any publications that result from
*  the use of this software or in any product that includes this
*  software. The names TMAP, NOAA and/or PMEL, however, may not be used
*  in any advertising or publicity to endorse or promote any products
*  or commercial entity unless specific written permission is obtained
*  from NOAA/PMEL/TMAP. The user also understands that NOAA/PMEL/TMAP
*  is not obligated to provide the user with any support, consulting,
*  training or assistance of any kind with regard to the use, operation
*  and performance of this software nor to provide the user with any
*  updates, revisions, new versions or "bug fixes".
*
*  THIS SOFTWARE IS PROVIDED BY NOAA/PMEL/TMAP "AS IS" AND ANY EXPRESS
*  OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
*  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
*  ARE DISCLAIMED. IN NO EVENT SHALL NOAA/PMEL/TMAP BE LIABLE FOR ANY SPECIAL,
*  INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
*  RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
*  CONTRACT, NEGLIGENCE OR OTHER TORTUOUS ACTION, ARISING OUT OF OR IN
*  CONNECTION WITH THE ACCESS, USE OR PERFORMANCE OF THIS SOFTWARE. 
*
* Ansley Manke
* Dec 1998
*
*
* This function computes fft phase spectrum for each time series.  Result
* time axis is a custom axis in period 1./time  The input variable must have
* the time axis specified explicitly in the function call e.g. 
*    LET sstp = fftp_sample(ssttim[l=1:492])
* and the time axis must be regular.

*  Note current limitations as of 1-Jan-2000
*   - Will have a utility to get the length of the input time axis at the
*     point when the custom freq axis is set up, to use in computing the
*     length of the frequency axis.  Currently need to specify explicitly, 
*     in the function call e.g. fftp_sample(sst[l=1:400]).

*  NOTE:
*  IT IS GENERALLY ADVISABLE TO INCLUDE EXPLICIT LIMITS WHEN WORKING WITH
*  FUNCTIONS THAT REPLACE AXES. FOR EXAMPLE, THE CONSIDER THE FUNCTION
*  SORTL(v). THE EXPRESSION
*       LIST/L=6:10 SORTL(v)
*  IS NOT EQUIVALENT TO
*       LIST SORTL(v[L=6:10])
*  THE FORMER WILL LIST THE 6TH THROUGH 10TH SORTED INDICES FROM THE ENTIRE
*  L RANGE OF VARIABLE V. THE LATTER WILL LIST ALL OF THE INDICES THAT
*  RESULT FROM SORTING v[L=6:10].
*  
* V5.53  *acm*  6/03 Correct the frequency axis:  Incorrect factor of
*                     1.001 in freqn = 1.001*yquist
*
* In this subroutine we provide information about
* the function.  The user configurable information 
* consists of the following:
*
* descr              Text description of the function
*
* num_args           Required number of arguments
*
* axis_inheritance   Type of axis for the result
*                       ( CUSTOM, IMPLIED_BY_ARGS, NORMAL, ABSTRACT )
*                       CUSTOM          - user defined axis
*                       IMPLIED_BY_ARGS - same axis as the incoming argument
*                       NORMAL          - the result is normal to this axis
*                       ABSTRACT        - an axis which only has index values
*
* piecemeal_ok       For memory optimization:
*                       axes where calculation may be performed piecemeal
*                       ( YES, NO )
* 
*
* For each argument we provide the following information:
*
* name               Text name for an argument
*
* unit               Text units for an argument
*
* desc               Text description of an argument
*
* axis_influence     Are this argument's axes the same as the result grid?
*                       ( YES, NO )
*
* axis_extend       How much does Ferret need to extend arg limits relative to result 
*


      SUBROUTINE fftp_sample_init(id)

      INCLUDE 'ferret_cmn/EF_Util.cmn'

      INTEGER id, arg

      CHARACTER*110 arg_desc

* **********************************************************************
*                                            USER CONFIGURABLE PORTION |
*                                                                      |
*                                                                      V
*                                                                      V
      CALL ef_set_desc(id, 'Computes fft phase' )

      CALL ef_set_num_args(id, 1)
      CALL ef_set_axis_inheritance(id, IMPLIED_BY_ARGS, 
     .     IMPLIED_BY_ARGS, IMPLIED_BY_ARGS, CUSTOM)
      CALL ef_set_piecemeal_ok(id, NO, NO, NO, NO)

      CALL ef_set_num_work_arrays(id, 4)

      arg = 1
      CALL ef_set_arg_name(id, arg, 'A')
      CALL ef_set_arg_unit(id, arg, ' ')
      WRITE (arg_desc, 10) 
   10 FORMAT ('Variable with regular time axis. Specify time ', 
     .         'explicitly e.g. fftp_sample(var[l=1,120])')

      CALL ef_set_arg_desc(id, arg, arg_desc)

      CALL ef_set_axis_influence(id, arg, YES, YES, YES, NO)


*                                                                     ^
*                                                                     |
*                                           USER CONFIGURABLE PORTION |
***********************************************************************

      RETURN 
      END


      SUBROUTINE fftp_sample_custom_axes(id)

      INCLUDE 'ferret_cmn/EF_Util.cmn'
      INTEGER id

* **********************************************************************
*                                            USER CONFIGURABLE PORTION |
*                                                                      |
*                      
*
*     Use utility functions to get grid information about the 
*     argument; use this info to determine the custom axis lo/hi/del 

      INTEGER nfreq_lo_l, nfreq_hi_l

      INTEGER arg_lo_ss(4,EF_MAX_ARGS), arg_hi_ss(4,EF_MAX_ARGS),
     .     arg_incr(4,EF_MAX_ARGS)

      INTEGER arg
      INTEGER nfreq, nd

      REAL yquist, freq1, freqn
      
      CHARACTER outunits*32
      REAL boxsize(1)
         
      CHARACTER ax_name(4)*16, ax_units(4)*16
      LOGICAL backward(4), modulo(4), regular(4)

      arg = 1
      CALL ef_get_arg_subscripts(id, arg_lo_ss, arg_hi_ss, arg_incr)

      CALL ef_get_axis_info(id, arg, ax_name, ax_units, backward,
     .     modulo, regular)

      CALL ef_get_box_size(id, arg, T_AXIS, arg_lo_ss(T_AXIS,arg), 
     .               arg_lo_ss(T_AXIS,arg), boxsize)
     

      IF ( arg_hi_ss(T_AXIS,arg) - arg_lo_ss(T_AXIS,arg) .EQ. 0 ) THEN
         nfreq_lo_l = 1
         nfreq_hi_l = 2
      ELSE
         nfreq_lo_l = arg_lo_ss(T_AXIS,arg)
         nfreq_hi_l = arg_hi_ss(T_AXIS,arg)
      ENDIF

      nd = abs(nfreq_hi_l - nfreq_lo_l) + 1

C  The FFT code returns frequencies W(k) for k=1 to N/2, with N/2 rounded down

C  Set label for the frequency axis CYC/units.

      outunits = 'CYC/' // ax_units(T_AXIS)

      CALL ef_set_freq_axis (id, T_AXIS, nd, boxsize(1), outunits, NO)
                     outunits, NO)

*                                                                      ^
*                                                                      |
*                                            USER CONFIGURABLE PORTION |
* **********************************************************************

      RETURN 
      END


*
* In this subroutine we provide information about the lo and hi
* limits associated with each abstract or custom axis.   The user 
* configurable information consists of the following:
*
* lo_ss               lo subscript for an axis
*
* hi_ss               hi subscript for an axis
*

      SUBROUTINE fftp_sample_result_limits(id)

      INCLUDE 'ferret_cmn/EF_Util.cmn'
      INCLUDE 'ferret_cmn/EF_mem_subsc.cmn'

      INTEGER id

* **********************************************************************
*                                           USER CONFIGURABLE PORTION |
*                                                                     |
*                                                                     V

      INTEGER ntime, nfreq

      INTEGER arg
      INTEGER arg_lo_ss(4,EF_MAX_ARGS), arg_hi_ss(4,EF_MAX_ARGS),
     .     arg_incr(4,EF_MAX_ARGS)


*     Use utility functions to get context information about the argument.

      CALL ef_get_arg_subscripts(id, arg_lo_ss, arg_hi_ss, arg_incr)

      nfreq = 1

      arg = 1
      ntime = arg_hi_ss(T_AXIS,arg) - arg_lo_ss(T_AXIS,arg) + 1

C  The FFT code returns frequencies W(k) for k=1 to N/2, with N/2 rounded down

      nfreq = ntime/ 2
      if (ntime .ne. nfreq*2) nfreq = (ntime+1)/2 ! see FFTPACK comments in rfftf

      CALL ef_set_axis_limits(id, T_AXIS, 1, nfreq)

*                                                                      ^
*                                                                      |
*                                            USER CONFIGURABLE PORTION |
* **********************************************************************

      RETURN 
      END

*
* In this subroutine we request an amount of storage to be supplied
* by Ferret and passed as an additional argument.
*
      SUBROUTINE fftp_sample_work_size(id)

      INCLUDE 'ferret_cmn/EF_Util.cmn'
      INCLUDE 'ferret_cmn/EF_mem_subsc.cmn'

      INTEGER id

* **********************************************************************
*                                            USER CONFIGURABLE PORTION |
*                                                                      |
* 
* Set the work arrays,  X/Y/Z/T dimensions
*
* ef_set_work_array_dims(id,array #,xlo,ylo,zlo,tlo,xhi,yhi,zhi,thi)
*
      INTEGER mtdat, mtwork
      INTEGER arg_lo_ss(4,1:EF_MAX_ARGS), arg_hi_ss(4,1:EF_MAX_ARGS),
     .     arg_incr(4,1:EF_MAX_ARGS)

      CALL ef_get_arg_subscripts(id, arg_lo_ss, arg_hi_ss, arg_incr)

      mtdat = 1 + arg_hi_ss(T_AXIS,ARG1) - arg_lo_ss(T_AXIS,ARG1)

      mtwork = 2.5* mtdat + 15
  
* a
      CALL ef_set_work_array_dims (id, 1, 1, 1, 1, 1, mtdat, 1, 1, 1)

* b
      CALL ef_set_work_array_dims (id, 2, 1, 1, 1, 1, mtdat, 1, 1, 1)

* wft
      CALL ef_set_work_array_dims (id, 3, 1, 1, 1, 1, mtwork, 1, 1, 1)

* ts
      CALL ef_set_work_array_dims (id, 4, 1, 1, 1, 1, mtdat, 1, 1, 1)

*                                                                      ^
*                                                                      |
*                                            USER CONFIGURABLE PORTION |
* **********************************************************************

      RETURN
      END


*
* In this subroutine we compute the result
*
      SUBROUTINE fftp_sample_compute(id, arg_1, result, a, b, wft, ts)

      INCLUDE 'ferret_cmn/EF_Util.cmn'
      INCLUDE 'ferret_cmn/EF_mem_subsc.cmn'

      INTEGER id, arg

      REAL bad_flag(1:EF_MAX_ARGS), bad_flag_result
      REAL arg_1(mem1lox:mem1hix, mem1loy:mem1hiy, 
     .           mem1loz:mem1hiz, mem1lot:mem1hit)
      REAL result(memreslox:memreshix, memresloy:memreshiy,
     .            memresloz:memreshiz, memreslot:memreshit)

* After initialization, the 'res_' arrays contain indexing information 
* for the result axes.  The 'arg_' arrays will contain the indexing 
* information for each variable's axes. 

      INTEGER res_lo_ss(4), res_hi_ss(4), res_incr(4)
      INTEGER arg_lo_ss(4,1:EF_MAX_ARGS), arg_hi_ss(4,1:EF_MAX_ARGS),
     .     arg_incr(4,1:EF_MAX_ARGS)


* **********************************************************************
*                                            USER CONFIGURABLE PORTION |
*                                                                      |
*                                                                      V
      CHARACTER ax_name(4)*16, ax_units(4)*16
      LOGICAL backward(4), modulo(4), regular(4)

*  Dimension work arrays

      REAL a(wrk1lox:wrk1hix, wrk1loy:wrk1hiy,
     .               wrk1loz:wrk1hiz, wrk1lot:wrk1hit)
      REAL b(wrk2lox:wrk2hix, wrk2loy:wrk2hiy,
     .               wrk2loz:wrk2hiz, wrk2lot:wrk2hit)
      REAL wft(wrk3lox:wrk3hix, wrk3loy:wrk3hiy,
     .               wrk3loz:wrk3hiz, wrk3lot:wrk3hit)
      REAL ts(wrk4lox:wrk4hix, wrk4loy:wrk4hiy,
     .               wrk4loz:wrk4hiz, wrk4lot:wrk4hit)

      REAL aa, bb,  rad
      INTEGER nd, nf
      INTEGER i,j,k,l
      INTEGER i1, j1, k1, l1

      CHARACTER*80 err_msg

   40 FORMAT ('FFTP encountered missing data at (i,j,k,l)', 4I5)

      rad = 180.0/ 3.141592654

      CALL ef_get_res_subscripts(id, res_lo_ss, res_hi_ss, res_incr)
      CALL ef_get_arg_subscripts(id, arg_lo_ss, arg_hi_ss, arg_incr)
      CALL ef_get_bad_flags(id, bad_flag, bad_flag_result)


*  number of time points.

      arg = 1
      nd = (arg_hi_ss(T_AXIS,arg) - arg_lo_ss(T_AXIS,arg) + 1)
      nf = nd/ 2

*  Check that the time axis is regular.

      CALL ef_get_axis_info (id, 1, ax_name, ax_units, backward,
     .     modulo, regular)

      IF (.NOT. regular(T_AXIS)) THEN
            WRITE (err_msg, *) 'Time axis must be a regular axis'
            GO TO 999
      ENDIF

*  Set WFT for fft; prime factorization of ND and trig functions.

      CALL rffti (nd, wft)

      i1 = arg_lo_ss(X_AXIS,ARG1)
      DO 400 i=res_lo_ss(X_AXIS), res_hi_ss(X_AXIS)

         j1 = arg_lo_ss(Y_AXIS,ARG1)
         DO 300 j=res_lo_ss(Y_AXIS), res_hi_ss(Y_AXIS)

            k1 = arg_lo_ss(Z_AXIS,ARG1)
            DO 200 k=res_lo_ss(Z_AXIS), res_hi_ss(Z_AXIS)

*
* Calculate the FFT for each time series which have no missing data.
*
               l1 =arg_lo_ss(T_AXIS,ARG1)
               DO 100 l = 1, nd
                  IF (arg_1(i1,j1,k1,l1) .EQ. bad_flag(ARG1)) THEN
                     WRITE (err_msg, 40) i1,j1,k1,l
                     GO TO 999 
                  ENDIF

                  ts(l,1,1,1) = arg_1(i1,j1,k1,l1)
                  l1 = l1 + arg_incr(T_AXIS,ARG1)
 100           CONTINUE


               l1 = arg_lo_ss(T_AXIS,ARG1)
               l = res_lo_ss(T_AXIS)

               CALL four_re (nd, ts, a, b, wft)

               DO 110 l = res_lo_ss(T_AXIS), res_hi_ss(T_AXIS) 
                   aa = a(l,1,1,1)
                   bb = b(l,1,1,1)
                   result(i,j,k,l) = rad* ATAN2(-1.*bb, aa)
 110           CONTINUE

               k1 = k1 + arg_incr(Z_AXIS,ARG1)
 200        CONTINUE

            j1 = j1 + arg_incr(Y_AXIS,ARG1)
 300     CONTINUE

         i1 = i1 + arg_incr(X_AXIS,ARG1)
 400  CONTINUE

      RETURN

 999  CALL ef_bail_out (id, err_msg)
*                                                                      ^
*                                                                      |
*                                            USER CONFIGURABLE PORTION |
* **********************************************************************

      RETURN 
      END