LCNTR plots a contour plot of a uniformly sampled 2-d input array. LCNTR is similar to CNTRPLT but permits hardware line types. The input consists of a 2 dimensional grid of v values. A contour is determined by linearily interpolating the edges of the square formed by 4 adjacent points (see CNTRPLT). LCNTR connects the line segments of constant contour before plotting and can optionally label the contour lines with alphabetic codes or the numerical value of the contour. Log axes are available but data points are plotted using linear positioning. (Note: common block scale factors will be log values if the log axes are selected.)
When the contour levels are input (nl>0), contours can be suppressed in a region by setting the value of the input array greater than 1.E20. LCNTR uses the contouring routine GCONTR.
CALL LCNTR(v,ndx,ndy,nx,ny,nl,cl,n,m,iflag,iw,xl,yl,xt,nxt,yt,nyt, t,nt,xm,xx,ym,yx<<,ic>,l>) v (R): 2-d array of values dimensioned v(ndx,ndy) ndx,ndy (I): dimensions of data array nx,ny (I): number of points in each array dimension nl (I): number of uniformly spaced contour levels, < 0 : max and min of v are used to define contours. the (j)th contour is computed from max,min of input array according to, (j-1)*(max(v)-min(v))/(nl-1)+min(v) > 0 : number of contour levels specified in cl cl (R): array of contour levels dimensioned cl(nl) if nl < 0 contour levels used are (returned) in cl n (I): contour labeling option < 0 label with contour value (number with n digits to the right of the decimal point) = 0 no labels on contours > 0 label contours with ASCII characters (nl <= 26) m (I): minimum line segments before contour labeled (m > 1) iflag (I): option flag < 0 : do not close LONGLIB after plotting = 0 : close LONGLIB--no plot produced > 0 : close LONGLIB after plotting (magnitude) >10000 : do not initialize LONGLIB before plotting (1's digit) = 1 : plot x linear, y logarithmic (base 10) = 2 : plot x logarithmic, y linear = 3 : plot x logarithmic, y logarithmic = 4 : plot x linear, y linear (10's digit) = 0 : no axes or title plotted = 1 : axes with axis line/ticks on top and sides = 2 : plot solid cartesian grid = 3 : plot ticked cartesian grid without box = 4 : plot ticked cartesian grid with box = 5 : plot ticked cartesian grid, box w/axis ticks = 6 : plot without box or cartesian grid = 7 : plot solid logarithmic grid = 8 : plot dotted logarithmic grid = 9 : plot ticked logarithmic grid (100's) = 0 : Ask which screen device to use <> 0 : Screen Device Number (see FRAME) iw (I): working array dimensioned at least (2*nx*ny+1)/31 xl (R): x axis length in inches (integer valued) > 0 : use input scaling in xm,xx for axis < 0 : use smoothed input scaling in xm,xx for axis yl (R): y axis length in inches (integer valued) > 0 : use input scaling in ym,yx for axis < 0 : use smoothed input scaling in ym,yx for axis xt (C): x axis title string nxt (I): number of characters in xt < 0 : axis ticks on top of x axis = 0 : no axis > 0 : axis ticks on bottom of x axis (normal) yt (C): y axis title string nyt (I): number of characters in yt < 0 : axis ticks on right of y axis = 0 : no axis > 0 : axis ticks on left of y axis (normal) t (C): plot title string nt (I): number of characters in t (limited to 99 characters) < 0 : use color array = 0 : no title > 0 : do not use color array if |nt|/100 > 0 : use line type list xm (R): input minimum value of x axis xx (R): input maximum value of x axis ym (R): input minimum value of y axis yx (R): input maximum value of y axis (NOTE: color array accessed if nt < 0 or |nt|/100 >0) ic (I): color array ic(1) : color for grid ic(2) : color for axis lines ic(3) : color for axis numbers ic(4) : color for axis titles ic(5) : color for axis exponent ic(6) : color for title (return) ic(7) : color for contour line 1 ic(8) : color for contour line 2 ic(9) : etc. l (I): line type list for contours (accessed if |nt|/100>0) common /ccntrplt/xmr,dxr,ymr,dyr xmr (R): returned value of xmin dxr (R): returned value of scale factor (xmax-xmin)/xlen ymr (R): returned value of ymin dyr (R): returned value of scale factor (ymax-ymin)/ylen