CR10X Reference Manual
10-8
PAR.
DATA
NO.
TYPE
DESCRIPTION
01:
4
Number of values to move
02:
4
First source location
03:
2
Step of source
04:
4
First destination location
05:
2
Step of destination
Input locations altered:
Number of values of move
Instruction 55: Fifth Order Polynomial
This instruction evaluates a fifth order polynomial of the form:
F(X)=C0+C1X+C2X
2
+C3X
3
+C4X
4
+C5X
5
where C0 to C5 are the coefficients for the argument X raised to the zero to fifth
power, respectively. The magnitude of the user-entered coefficient is limited to a
range of ±0.000001 to ±999999. Polynomials with coefficients outside this range
can be modified by pre-scaling the X value by an appropriate factor to place the
coefficients within the entry range. Pre-scaling can also be used to modify co-
efficients which are very close to 0 in order to increase the number of significant
digits.
Older versions of Edlog and the CR10KD limit the number of
significant gigits that can be entered to 5 ( ±0.00001 to ±99999).
PAR.
DATA
NO.
TYPE
DESCRIPTION
01:
2
Repetitions
[REPS]
02:
4
Starting input location for X
[X]
03:
4
Destination input location for F(X)
[F(X) or Z]
04:
FP
C0 coefficient
[C0]
05:
FP
C1 coefficient
[C1]
06:
FP
C2 coefficient
[C2]
07:
FP
C3 coefficient
[C3]
08:
FP
C4 coefficient
[C4]
09:
FP
C5 coefficient
[C5]
Input locations altered: 1 per repetition
Instruction 56: Saturation Vapour Pressure
This instruction calculates saturation vapour pressure over water (SVP
w
) in
kilopascals from the air temperature (
o
C) and places it in an input location. The
algorithm for obtaining SVP
w
from air temperature (
o
C) is taken from: Lowe, Paul
R., 1977: An approximating polynomial for computation of saturation vapour
pressure. J. Appl. Meteor 16, 100-103.
Saturation vapour pressure over ice (SVP
i
) in kilopascals for a -50
o
C to 0
o
C
range can be obtained using Instruction 55 and the relationship:
SVP
i
= -.00486 + .85471 X + .2441 X
2
NOTE