Manual Reference Pages - lgaxs (3)
NAME
lgaxs(3f) - [M_calcomp:scientific] draw logarithmic axis (LICENSE:PD)
CONTENTS
Synopsis
Description
Options
Comments
Example
License
SYNOPSIS
subroutine lgaxs(xpage,ypage,ibcd,+-nchar,axlen,angle,firstv,deltav)
DESCRIPTION
LGAXS(3f) is a FORTRAN subroutine which draws a logarithmic axis with annotation in powers of ten. LGAXS(3f) is similar in operation to AXIS(3f).
OPTIONS
XPAGE,YPAGE are the coordinates, in inches, of the axis starting point. IBCD is the character data to be used as the axis title (may be one or more characters). It is centered and positioned parallel to the axis. NCHAR is the number of characters in the axis title. if NCHAR is:o negative, annotation is placed on the clockwise side of the axis (normally used for the X axis);
o positive, annotation is placed on the counterclockwise side of the axis (normally used for the Y axis).
AXLEN is the length of the axis, in inches. ANGLE is the angle, in degrees, at which the axis is to be drawn. (The axis is rotated about XPAGE,YPAGE). The X axis is at 0 degrees; the Y axis is at 90 degrees. FIRSTV is the value of annotation at the beginning of the axis. DELTAV is the number of log cycles per inch (the reciprocal of the length of one cycle, in inches). Equivalently this is the reciprocal of the length of one cycle.
if SCALOG() is used to scale a logarithmic array, VARRAY, then FIRSTV=VARRAY(NV*K+1), and DELTAV=VARRAY(NV*K+K+1) where NV is number of values used and K is repeat cycle of location of values in array, as described in SCALOG().
COMMENTS
A tick mark is placed on the axis for each power of ten and for each of the nine integer values between.
Annotation is placed at the tick marks as follows:
o If a cycle is not less than two inches long, the integer tick marks are annotated. o The power-of-ten tick marks are annotated in the form 10**N.
EXAMPLE
Sample program:
program demo_lgaxs use M_calcomp implicit none ! based on concepts of CALIFORNIA COMPUTER PRODUCTS, 1968 character(len=50) :: ibcd integer :: i, k integer :: inteq real :: a real :: angl real :: angle(19) real :: bang real :: beta real :: r(19) real :: theta real :: x real :: xx real :: xa,ya, xb,yb, xc,yc, xd,yd real :: xar(8)= [ 1.00, 2.00, 3.00, 4.00, 5.00, 6.00 , 0.0, 0.0 ] real :: yar(8)= [ 250.0, 110.0, 500.0, 900.0, 200.0, 140.0 , 0.0, 1.0 ] call plots(0.0,10.0,0.0,10.0) ! DRAW FRAME call plot(7.0,0.0,2) call plot(7.0,9.0,2) call plot(0.0,9.0,2) call plot(0.0,0.0,2) ! DRAW COMMENTS ibcd=’USING SCALG, LGAXS, AND LGLIN SUBROUTINES’ call symbol(0.7,8.25,0.14,ibcd,inteq,0.0,42) ibcd=’USING POLAR SUBROUTINE’ call symbol(0.7,3.80,0.14,ibcd,inteq,0.0,22) ! AXIS IS DRAWN ibcd=’ALTITUDE’ call axis(1.0,4.75,ibcd,-8,5.0,0.0,0.0,25.0) call scalg(yar,3.0,6,1) ibcd=’TEMPERATURE’ call lgaxs(1.0,4.75,ibcd,11,3.0,90.0,yar(7),yar(8)) call scale(xar,5.0,6,1) call plot(1.0,4.75,-3) call lglin(xar,yar,6,1,0,1,1) call plot(-1.0,-4.75,-3) ! POLAR SUBROUTINE IS USED x=0.0 do k=1,19 theta=x*0.0174533 r(k)=2.0*(1.0-cos(theta)) angle(k)=theta x=x+10.0 enddo call plot(5.0,0.75,-3) call polar(r,angle,19,1,0,1,0.0,1.0) angl =30.0 a=1.0 do i=1,5 theta=angl *0.0174533 xa=cos(theta) ya=sin(theta) call plot(xa,ya,3) xb=1.1*xa yb=1.1*ya call plot(xb,yb,2) xc=xb+0.05*xa yc=yb+0.05*ya if((i-3).gt.0)then a=1.5 endif beta=1.570797-theta xd=xc-0.105*a*cos(beta) yd=yc+0.105*a*sin(beta) bang=270.0+angl call number(xd,yd,0.105,angl, bang,-1) angl =angl +30.0 enddo xx=0.0 do i=1,19 angle(i) = xx*0.0174533 r(i) = 1.0 xx=xx+10.0 enddo call polar(r,angle,19,1,0,1,0.0,1.0) call plot(-5.0,-0.75,-3) ! AXIS IS DRAWN ibcd=’’ call axis(1.0,0.75,ibcd,-1,4.0,0.0,4.0,-1.0) call axis(5.0,0.75,ibcd,-1,1.0,0.0,0.0,1.0) ibcd=’RADIUS=2*(1-COS(ANGLE))’ call symbol(3.75,3.5,0.09,ibcd,inteq,0.0,23) call plot(11.0,0.0,999) end program demo_lgaxs
LICENSE
Public Domain
| lgaxs (3) | March 11, 2021 |
