IBM 1130 User Manual page 573

Section
Subsections Page
70
60
I
10 01
FORTRAN EXECUTION TIMES
listings, and count the average number of times the
operations shown in Figure 70.33 will be executed.
Then use the times shown in Figure 70.33 to
estimate the total execution time.
Processing
It is possible to estimate the length of time it will
take to execute an arithmetic block of FOR TRAN
coding. Inspect your coding sheets, or program
Note that you must consider the probability of
execution, not just the number of appearances. If
a certain loop will be executed
15
times, on the
Operation
GET
PUT
EDIT
MOVE
FILL
WHOLE
NCOMP
NZONE
ICOMP
NSIGN
ADD
SUB
MPY
DIV
A1DEC
DECA1
A1A3
A3A1
PACK
UNPAC
DPACK
DUNPK
SIN
COS
ATAN
SQRT
EXP
ALOG
TANH
Approximate* time in
Microseconds,** each execution
(time for standard precision
use in parentheses)
Operation
Approximate* time in
Microseconds,** each execution
(time for standard precision
use in parentheses)
2250 + 2190C
3450 + 3090 C
630+ 90S+ 180M
300+ 45 C
300+ 30 C
1400
250+ 75 C
350
500 + 95 C
240
2160+ 216 L
2160+ 216 L
2400 + 120 P
4000 + 0(445 + 667 DIV)
700+ 54 A
180+ 117 A
470 + 1084 A
545 + 156 A
360+ 63A
420 + 66 A
3920
3600
5400 (3000)
5900 (3400)
8900 (5300)
10400 (4500)
4400 (2000)
8000 (5100)
8100 (4300)
real =
integer
=
+real
+integer
-real
-integer
*real
*integer
/real
/integer
real**real
integer**integer
FLOAT
FIX
subscript (no variabl e)
subscript (one variable)
subscript (two variables)
subscript (three variables)
DO
IF (real)
I F (integer)
GO TO
GO TO ( ), N
N
C
=
=
The number of times through the DO loop
Length of the field, in characters
S
M
P
A
0
L
0
DIV
=
=
=
=
=
=
=
=
Length of the source field
Length of the edit mask
Length of the multiplier field x length of the multiplicand field
(significant digits only - don't count leading zeros)
Length of the A 1 field
Length of the packed decimal (04) field
Length of the longer of the two fields (significant digits only -
don't count leading zeros)
Number of significant digits in the quotient (result) field
Number of significant digits in the divisor (denominator) field
300 (360)
22
440(460
12
490 (560)
12
790 (560)
30
2100 (800)
80
13300 (8000)
4700 (3800)
330
140
25
280
390
530
22
+
50 N
190 (210)
30
7
7
* Most timings are approximate and are based on test runs of "typical" cases, using fields of "average" size,
magnitude, etc. Unusual cases may (or may not) differ significantly from the timings obtained from the
given equations. This is particularly true of the decimal arithmetic routines (ADD, SUB, MPY, DIV).
** Based on 3.6-microsecond CPU cycle speed. Multiply by 0.6 to obtain timings on 2.2-microsecond CPU.
Figure 70.33.