1funtablerowput(3) SAORD Documentation funtablerowput(3)
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6 FunTableRowPut - put Funtools rows
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9 int FunTableRowPut(Fun fun, void *rows, int nev, int idx, char *plist)
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12 The FunTableRowPut() routine writes rows to a FITS binary table, taking
13 its input from an array of user structs that contain column values
14 selected by a previous call to FunColumnSelect(). Selected column val‐
15 ues are automatically converted from native data format to FITS data
16 format as necessary.
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18 The first argument is the Fun handle associated with this row data.
19 The second rows argument is the array of user structs to output. The
20 third nrow argument specifies the number number of rows to write. The
21 routine will write nrow records, starting from the location specified
22 by rows.
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24 The fourth idx argument is the index of the first raw input row to
25 write, in the case where rows from the user buffer are being merged
26 with their raw input row counterparts (see below). Note that this idx
27 value is has nothing to do with the row buffer specified in argument 1.
28 It merely matches the row being written with its corresponding (hidden)
29 raw row. Thus, if you read a number of rows, process them, and then
30 write them out all at once starting from the first user row, the value
31 of idx should be 0:
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33 Ev ebuf, ev;
34 /* get rows -- let routine allocate the row array */
35 while( (ebuf = (Ev)FunTableRowGet(fun, NULL, MAXROW, NULL, &got)) ){
36 /* process all rows */
37 for(i=0; i<got; i++){
38 /* point to the i'th row */
39 ev = ebuf+i;
40 ...
41 }
42 /* write out this batch of rows, starting with the first */
43 FunTableRowPut(fun2, (char *)ebuf, got, 0, NULL);
44 /* free row data */
45 if( ebuf ) free(ebuf);
46 }
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48 On the other hand, if you write out the rows one at a time (possibly
49 skipping rows), then, when writing the i'th row from the input array of
50 rows, set idx to the value of i:
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52 Ev ebuf, ev;
53 /* get rows -- let routine allocate the row array */
54 while( (ebuf = (Ev)FunTableRowGet(fun, NULL, MAXROW, NULL, &got)) ){
55 /* process all rows */
56 for(i=0; i<got; i++){
57 /* point to the i'th row */
58 ev = ebuf+i;
59 ...
60 /* write out the current (i.e., i'th) row */
61 FunTableRowPut(fun2, (char *)ev, 1, i, NULL);
62 }
63 /* free row data */
64 if( ebuf ) free(ebuf);
65 }
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67 The final argument is a param list string that is not currently used.
68 The routine returns the number of rows output. This should be equal to
69 the value passed in the third nrow</B argument.
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71 When FunTableRowPut() is first called for a given binary table, Fun‐
72 tools checks to see of the primary header has already been written
73 (either by writing a previous row table or by writing an image.) If
74 not, a dummy primary header is written to the file specifying that an
75 extension should be expected. After this, a binary table header is
76 automatically written containing information about the columns that
77 will populate this table. In addition, if a Funtools reference handle
78 was specified when this table was opened, the parameters from this Fun‐
79 tools reference handle are merged into the new binary table header.
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81 In a typical Funtools row loop, you read rows using FunTableRowGet()()
82 and write rows using FunTableRowPut(). The columns written by FunT‐
83 ableRowPut()() are those defined as writable by a previous call to Fun‐
84 ColumnSelect(). If that call to FunColumnSelect also specified
85 merge=[update⎪replace⎪append], then the entire corresponding raw input
86 row record will be merged with the output row according to the merge
87 specification (see FunColumnSelect() above).
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89 A call to write rows can either be done once, after all rows in the
90 input batch have been processed, or it can be done (slightly less effi‐
91 ciently) one row at a time (or anything in between). We do recommend
92 that you write all rows associated with a given batch of input rows
93 before reading new rows. This is required if you are merging the out‐
94 put rows with the raw input rows (since the raw rows are destroyed with
95 each successive call to get new rows).
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97 For example:
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99 Ev buf, ev;
100 ...
101 /* get rows -- let routine allocate the row array */
102 while( (buf = (Ev)FunTableRowGet(fun, NULL, MAXROW, NULL, &got)) ){
103 /* point to the i'th row */
104 ev = buf + i;
105 .... process
106 }
107 /* write out this batch of rows */
108 FunTableRowPut(fun2, buf, got, 0, NULL);
109 /* free row data */
110 if( buf ) free(buf);
111 }
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113 or
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115 Ev buf, ev;
116 ...
117 /* get rows -- let routine allocate the row array */
118 while( (buf = (Ev)FunTableRowGet(fun, NULL, MAXROW, NULL, &got)) ){
119 /* process all rows */
120 for(i=0; i<got; i++){
121 /* point to the i'th row */
122 ev = buf + i;
123 ... process
124 /* write out this batch of rows with the new column */
125 if( dowrite )
126 FunTableRowPut(fun2, buf, 1, i, NULL);
127 }
128 /* free row data */
129 if( buf ) free(buf);
130 }
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132 Note that the difference between these calls is that the first one out‐
133 puts got rows all at once and therefore passes idx=0 in argument four,
134 so that merging starts at the first raw input row. In the second case,
135 a check it made on each row to see if it needs to be output. If so,
136 the value of idx is passed as the value of the i variable which points
137 to the current row being processed in the batch of input rows.
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139 As shown above, successive calls to FunTableRowPut() will write rows
140 sequentially. When you are finished writing all rows in a table, you
141 should call FunFlush() to write out the FITS binary table padding. How‐
142 ever, this is not necessary if you subsequently call FunClose() without
143 doing any other I/O to the FITS file.
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145 Note that FunTableRowPut() also can be called as FunEventsPut(), for
146 backward compatibility.
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149 See funtools(n) for a list of Funtools help pages
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153version 1.4.2 January 2, 2008 funtablerowput(3)