Natural Logarithm Operation On Floating-Point Data (Double Precision Logd(P)) - Mitsubishi MELSEC Q Series Programming Manual

7.12.24
Natural logarithm operation on floating-point data
(Double precision) (LOGD(P))
LOGD(P)
LOGD
LOGDP
Settiing
Data
S
D
Function
(1) Returns the natural logarithm of the value designated by
operation results at device designated by
(2) Only positive values can be designated by
numbers.)
(3) When the operation results in -0 or an underflow, the result is processed as 0.
Operation Error
(1) In any of the following cases, an operation error occurs, the error flag (SM0) turns ON, and
an error code is stored into SD0.
• The value designated by
• The value designated by
• The value of the specified device is not in the following range:
0,2
• The value of the designated device is
• The result exceeds the following range (Operation results in an overflow):
1024
2
Command
Command
: Data of which the natural logarithm is obtained or head number of the devices where the data is stored
S
(real number)
: Head number of the devices where the operation result will be stored (real number)
D
Internal Devices
R, ZR
Bit Word
––
––
S +3 S +2 S +1
log
(
64-bit floating-point
real number
is negative.
S
is 0.
S
-1022
| value of specified device | < 2
| Operation result |
High
Basic
performance
LOGD
LOGDP
J \
U \G
Bit Word
––
––
S
.
D
S D +3 D +2
) (
64-bit floating-point
real number
. (Operation cannot be performed on negative
S
1024
0.
LOGD(P)
Process
Redundant Universal
S D
S D
Constants
Zn Other
E
––
taking (e) as base, and stores
D +1 D
)
(Error code: 4100)
(Error code: 4100)
(Error code: 4140)
(Error code: 4140)
(Error code: 4141)
7-297
1
2
LCPU
3
4
6
6
7
––
––
8