Description:
This routine returns the value of a scalar
GSD item. The item must be specified by the file desciptor, item descriptor array, data array and item
number.
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| t | type | Fortran | GSD |
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| b | char | byte | byte |
| l | char | logical1 | logical |
| w | short | integer2 | word |
| i | int | integer4 | integer |
| r | float | real4 | real |
| d | double | real8 | double |
| c | char[16] | character16 | char |
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This routine does not convert between types. If the type of the GSD item does not match the type of
the routine, then it returns with an error.
It is possible to get only part of the array. Although the part can be specified in terms of an
N-dimensional array, this routine does not take a proper N-D section of the array. The
caller can specify the start pixel in N dimensions and the end pixel in N dimensions.
These two pixels will be converted to memory locations and all memory between the
two is returned. This emulates the old GSD library. It is useful really only for parts
of 1-D arrays, parts of rows, or single pixels.
Invocation
int gsdGet1{blwird}( void
file_dsc, void
item_dsc, char
data_ptr, int itemno,
int ndims, int dimvals,
int start,
int end,
type
values, int
actvals );
Arguments
void file_dsc (Given)
The GSD
file descriptor.
void item_dsc
(Given)
The array of GSD item descriptors related to the GSD file.
char
data_ptr (Given)
The buffer with all the data from the GSD file.
int itemno (Given)
The number of the item in the GSD file.
int ndims (Given)
The dimensionality the calling routine uses to specify the start and end elements.
int
dimvals
(Given)
The array of ndims dimensions (array sizes along each axis).
int
start
(Given)
The array indices for the first element.
int
end
The array indices for the last element.
type
value
(Returned)
The data values. The calling routine must make sure that sufficient
memory is provided. Thus it must find out the data type and array size before calling
this routine. If the data type is character, then the routine returns a byte buffer with all
strings concatenated. There are no string terminators in the buffer and there is none at
the end. Each string is 16 byte long and immediately followed by the next string.
int
actvals
(Returned)
The number of array values returned. This saves the caller to work out how
many array elements correspond to start and end given the dimvals.
Returned Value
int
gsdGet1t();
Status.
-
[1:] Failure to read the item values.
-
[2:] Numbered item cannot be found.
-
[4:] Given start and end are inconsistent.
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[0:] Otherwise.
Prototype
available via #include "gsd.h"
Copyright
Copyright
(C) 1986-1999 Particle Physics and Astronomy Research Council. All Rights Reserved.