sacio.c File Reference

sac I/O and manipulation More...

Macros
#define	ERROR_NOT_A_SAC_FILE   1317
	Not a sac file.
#define	ERROR_OVERWRITE_FLAG_IS_OFF   1303
	Overwrite flag, lovrok is set to 0.
#define	ERROR_WRITING_FILE   115
	Error writing sac file.
#define	ERROR_READING_FILE   114
	Error reading sac file.
#define	ERROR_FILE_DOES_NOT_EXIST   108
	Error file does not exist.
#define	ERROR_OPENING_FILE   101
	Error opening sac file.
#define	SAC_OK   0
	Success, everything is ok.
#define	SAC_HEADER_SIZEOF_NUMBER   (sizeof(float))
	Size of header values in bytes.
#define	SAC_DATA_SIZE   SAC_HEADER_SIZEOF_NUMBER
	Size of data values in bytes.
#define	SAC_HEADER_VERSION_6   6
	Sac version no 6.
#define	SAC_HEADER_VERSION_7   7
	Sac version no 7.
#define	SAC_HEADER_MAJOR_VERSION   SAC_HEADER_VERSION_6
	Current Major sac version number.
#define	SAC_HEADER_MAX_VERSION   SAC_HEADER_VERSION_7
	Current Maximum sac version number.
#define	SAC_VERSION_LOCATION   76
	Offset in 4-byte words of the header version.
#define	MIN(a, b)   ((a < b) ? a : b )
	Minimum of two values.
#define	MAX(a, b)   ((a > b) ? a : b )
	Maximum of two values.
#define	B(s)   sac_float(s, SAC_B)
	Get begin value.
#define	E(s)   sac_float(s, SAC_E)
	Get end value.
#define	DT(s)   sac_float(s, SAC_DELTA)
	Get delta time value.
#define	SAC_HEADER_FLOATS   70 /* 4 bytes (real or float) */
#define	SAC_HEADER_INTEGERS   15
#define	SAC_HEADER_ENUMS   20
#define	SAC_HEADER_LOGICALS   5
#define	SAC_HEADER_STRINGS   24 /* 9 bytes (characters) actually 23 + 1 */
#define	SAC_HEADER_NUMBERS   ( SAC_HEADER_FLOATS + SAC_HEADER_INTEGERS + SAC_HEADER_ENUMS + SAC_HEADER_LOGICALS )
#define	X(name, key)   z->key = SAC_FLOAT_UNDEFINED;
	X-Macro for sac_f64_new() More...
#define	X(name, key)   case SAC_##name: s->h->key = (float) value; break;
	X-Macro for sac_f64_new() More...
#define	X(name, key)   case SAC_##name: s->z->key = value; s->h->key = (float) value; break;
	X-Macro for sac_f64_new() More...
#define	X(name, key)   case SAC_##name: *v = s->h->key; break;
	X-Macro for sac_f64_new() More...
#define	X(name, key)   case SAC_##name: *v = s->z->key; break;
	X-Macro for sac_f64_new() More...
#define	X(name, key)   s->h->key = (float) s->z->key;
	X-Macro for sac_f64_new() More...
#define	X(name, key)   s->z->key = s->h->key;
	X-Macro for sac_f64_new() More...
#define	COPY_MOVE(dst, src, n)
#define	SAC_ALPHA_FLOAT_LINES   14
#define	SAC_ALPHA_INT_LINES   8
#define	SAC_ALPHA_STRING_LINES   8
#define	SAC_ALPHA_FLOAT_FMT   "%#15.7g"
#define	SAC_ALPHA_INT_FMT   "%10d"
#define	SAC_ALPHA_STRING_FMT   "%8s"
#define	SAC_ALPHA_DOUBLE_FMT   "%.17g"
#define	SAC_HEADER_SIZE   632
	Size of header.
#define	X(name, key)   SAC_##name ,
	X-Macro for sac_f64_new() More...
#define	START_BEFORE   1<<0
	Start Time is before Begin value (B)
#define	START_INSIDE   1<<1
	Start Time is between Begin (B) and End Value (E)
#define	START_AFTER   1<<2
	Start Time is after End value (E)
#define	END_BEFORE   1<<3
	End Time is before Start time (B)
#define	END_INSIDE   1<<4
	End Time is between Begin (B) and End Value (E)
#define	END_AFTER   1<<5
	End Time is after End Value (E)

Functions
void	sac_write_alpha (sac *s, char *filename, int *nerr)
	Write a sac file in alpha-numeric format. More...
sac *	sac_read_alpha (char *filename, int *nerr)
	Read a alpha-numeric sac file. More...
sac *	sac_cut (sac *sin, char *c1, double t1, char *c2, double t2, enum CutAction cutact, int *nerr)
	cut a sac file More...

Detailed Description

sac I/O and manipulation

Macro Definition Documentation

COPY_MOVE

#define COPY_MOVE	(		dst,
			src,
			n
	)

Value:

do {   \
        memcpy(dst, src, n);          \
        dst[n] = 0;                   \
        src += n;                     \
        dst += (n+1);                 \
    } while(0) ;

SAC_HEADER_ENUMS

#define SAC_HEADER_ENUMS   20

Parameters

SAC_HEADER_ENUMS

Number of Enumerated values in the SAC Header Size: SAC_HEADER_SIZEOF_NUMBER bytes

SAC_HEADER_FLOATS

#define SAC_HEADER_FLOATS   70 /* 4 bytes (real or float) */

Parameters

SAC_HEADER_FLOATS

Number of Floating point values in the SAC Header Size: SAC_HEADER_SIZEOF_NUMBER bytes

SAC_HEADER_INTEGERS

#define SAC_HEADER_INTEGERS   15

Parameters

SAC_HEADER_INTEGERS

Number of Integer values in the SAC Header Size: SAC_HEADER_SIZEOF_NUMBER bytes

SAC_HEADER_LOGICALS

#define SAC_HEADER_LOGICALS   5

Parameters

SAC_HEADER_LOGICALS

Number of Logical values in the SAC Header Size: SAC_HEADER_SIZEOF_NUMBER bytes

SAC_HEADER_NUMBERS

#define SAC_HEADER_NUMBERS   ( SAC_HEADER_FLOATS + SAC_HEADER_INTEGERS + SAC_HEADER_ENUMS + SAC_HEADER_LOGICALS )

Parameters

SAC_HEADER_NUMBERS

Number of numeric values in the SAC Header Size: SAC_HEADER_SIZEOF_NUMBER bytes

SAC_HEADER_STRINGS

#define SAC_HEADER_STRINGS   24 /* 9 bytes (characters) actually 23 + 1 */

Parameters

SAC_HEADER_STRINGS

Number of strings in the SAC Header. The number here is in reality one less as the number below as of header version 6. The second value, the event name is twice as long as any other characer string

X [1/8]

#define X	(		name,
			key
	)		z->key = SAC_FLOAT_UNDEFINED;

X-Macro for sac_f64_new()

X-Macro for sac_f32_new()

X [2/8]

#define X	(		name,
			key
	)		case SAC_##name: s->h->key = (float) value; break;

X-Macro for sac_f64_new()

X-Macro for sac_f32_new()

X [3/8]

#define X	(		name,
			key
	)		case SAC_##name: s->z->key = value; s->h->key = (float) value; break;

X-Macro for sac_f64_new()

X-Macro for sac_f32_new()

X [4/8]

#define X	(		name,
			key
	)		case SAC_##name: *v = s->h->key; break;

X-Macro for sac_f64_new()

X-Macro for sac_f32_new()

X [5/8]

#define X	(		name,
			key
	)		case SAC_##name: *v = s->z->key; break;

X-Macro for sac_f64_new()

X-Macro for sac_f32_new()

X [6/8]

#define X	(		name,
			key
	)		s->h->key = (float) s->z->key;

X-Macro for sac_f64_new()

X-Macro for sac_f32_new()

X [7/8]

#define X	(		name,
			key
	)		s->z->key = s->h->key;

X-Macro for sac_f64_new()

X-Macro for sac_f32_new()

X [8/8]

#define X	(		name,
			key
	)		SAC_##name ,

X-Macro for sac_f64_new()

X-Macro for sac_f32_new()

Function Documentation

sac_cut()

sac* sac_cut	(	sac *	sin,
		char *	c1,
		double	t1,
		char *	c2,
		double	t2,
		enum CutAction	cutact,
		int *	nerr
	)

cut a sac file

cut a sac file and return a new sac file

Parameters

sin	sac file
c1	reference time pick for start time
t1	relative time from c1
c2	reference time pick for end time
t2	relative time from c2
cutact	Behavior of cut CutNone = 0 CutFatal = 1 CutUseBe = 2 CutFillZero = 3
nerr	status code 0 on success Might be non-zero when using CutUseBE

Returns

newly cut sac file

Note

Time pick reference

• "Z" - Actual time
• "B" - Begin time
• "E" - End time
• "O" - Origin time
• "A" - First arrival time
• "F" - Final arrival time: SAC_F value
• "T0" to "T9" - t0 to t9 arrival times

Example of cutting a sac file

int nerr = 0;
double b = 0, e = 0;
sac *cut = NULL;

sac *s = sac_read("t/test_io_small.sac", &nerr);
assert_eq(nerr, 0);

// Cut the sac file, returning a new file
cut = sac_cut(s, "Z", 10.0, "Z", 30.0, CutUseBE, &nerr);

sac_get_float(cut, SAC_B, &b);
sac_get_float(cut, SAC_E, &e);
assert_eq(b, 10.0);
assert_eq(e, 30.0);

sac_read_alpha()

sac* sac_read_alpha	(	char *	filename,
		int *	nerr
	)

Read a alpha-numeric sac file.

Read a sac file in alpha-numeric format

Parameters

filename	alpha numeric sac file to read from
nerr	error status code

Returns

sac file, NULL on error

Example of reading an alpha-numeric sac file

int nerr = 0;
sac *s = sac_read_alpha("t/test_spec_alpha.sac", &nerr);
assert_eq(nerr, 0);
assert_ne(s, NULL);

Reading a non-existant file returns a NULL pointer and nerr is set to 101

int nerr = 0;
sac *s = sac_read_alpha("non-existant-file", &nerr);
assert_eq(nerr, 101);
assert_eq(s, NULL);

Reading a file that is not a alpha-numeric file returns a NULL pointer and nerr is set to 1319

int nerr = 0;
sac *s = sac_read_alpha("t/test_io_small.sac", &nerr);
assert_eq(nerr, 1319);
assert_eq(s, NULL);

sac_write_alpha()

void sac_write_alpha	(	sac *	s,
		char *	filename,
		int *	nerr
	)

Write a sac file in alpha-numeric format.

Write a sac file into an alpha-numeric format

Parameters

s	sac file to write
filename	file to write to
nerr	error status code

int nerr = 0;
sac *s = sac_read("t/test_io_small.sac", &nerr);
assert_eq(nerr, 0);

// Write the sac file into alpha-numeric format
sac_write_alpha(s, "t/test_io_small_alpha.sac.tmp", &nerr);
assert_eq(nerr, 0);