multiplot.pro

basic median filter simulation

    ; number of plots left in the grid
    if n_elements(nleft) eq 1 then init = (nleft eq 0) else init = 1
    if (n_elements(pmulti) eq 2) or (n_elements(pmulti) eq 5) then init = 1
    if (n_elements(!p.multi) eq 5) then begin
        if (!p.multi[1] gt 0) and (!p.multi[2] gt 0) then begin
            init = (!p.multi[0] eq 0) 
        endif
    endif

    ; initialize if we are on the first plot
    if init or keyword_set(initialize) then begin
        case n_elements(pmulti) of
            0:begin
                if n_elements(!p.multi) eq 1 then return ; NOTHING TO SET
                if n_elements(!p.multi) ne 5 then begin
                    message,'Bogus !p.multi; aborting.'
                endif
                nplots = !p.multi[1:2] > 1
                if keyword_set(rowmajor) then begin
                    colmajor = 0 
                endif else begin
                    colmajor = !p.multi[4] eq 0
                endelse
            end
            2:begin
                nplots = pmulti
                colmajor = not keyword_set(rowmajor) 
            end
            5:begin
                nplots = pmulti[1:2]
                if keyword_set(rowmajor) then begin
                    colmajor = 0 
                endif else begin
                    colmajor = pmulti[4] eq 0
                endelse
            end
            else: message,'pmulti can only have 0, 2, or 5 elements.'
        endcase

        pposition = !p.position   ; save sysvar to be altered
        xtickname = !x.tickname
        ytickname = !y.tickname

        ; keep original values for resetting
        xtickformat_orig = !x.tickformat
        ytickformat_orig = !y.tickformat

        ; what will we actually plot when ticks are exposed?
        if n_elements(xtickformat_in) ne 0 then begin
            xtickformat=xtickformat_in
        endif else begin
            xtickformat=xtickformat_orig
        endelse
        if n_elements(ytickformat_in) ne 0 then begin
            ytickformat=ytickformat_in
        endif else begin
            ytickformat=ytickformat_orig
        endelse

        pdotmulti = !p.multi
        nleft = nplots[0]*nplots[1] ; total # of plots
        !p.position = 0           ; reset
        !p.multi = 0

        ; set window & region
        plot,/nodata,xstyle=4,ystyle=4,!x.range,!y.range,/noerase	

        px = !x.window*!d.x_vsize
        py = !y.window*!d.y_vsize
        xsize = px[1] - px[0]
        ysize = py[1] - py[0]

        ; in normlized coordinates
        nmargins = [min(!x.window)-min(!x.region), $ 
                    min(!y.window)-min(!y.region), $
                    max(!x.region)-max(!x.window), $
                    max(!y.region)-max(!y.window)]

        ;in device coord
        margins = nmargins
        margins[0] = nmargins[0]*!d.x_vsize
        margins[2] = nmargins[2]*!d.x_vsize
        margins[1] = nmargins[1]*!d.y_vsize
        margins[3] = nmargins[3]*!d.y_vsize

        noerase = !p.noerase
        !p.noerase = 1            ; !p.multi does the same

        if keyword_set(verbose) then begin
            major = ['across then down (column major).',$
                     'down then across (row major).']
                 if colmajor then index = 0 else index = 1
                 message,/inform,'Initialized for '+strtrim(nplots[0],2) $
                     +'x'+strtrim(nplots[1],2)+', plotted '+major[index]
        endif

        if keyword_set(initialize) then return
    endif

    ;
    ; Define the plot region without using !p.multi.
    ;

    cols = nplots[0]              ; for convenience
    rows = nplots[1]
    nleft = nleft - 1             ; decrement plots remaining
    cur = cols*rows - nleft       ; current plot #: 1 to cols*rows

    ; device coords per plot
    idx = [(!d.x_vsize-margins[0]-margins[2])/cols, $
           (!d.y_vsize-margins[1]-margins[3])/rows] 

    ;; force to be square if requested
    if sqplot then begin 
        if idx[0] lt idx[1] then idx[1]=idx[0] else idx[0]=idx[1]
    endif 

    if colmajor then begin        ; location in matrix of plots
        col = cur mod cols
        if col eq 0 then col = cols
        row = (cur-1)/cols + 1
    endif else begin              ; here (1,2) is 1st col, 2nd row
        row = cur mod rows
        if row eq 0 then row = rows
        col = (cur-1)/rows + 1
    endelse


    pos = $
        [(col-1)*idx[0], (rows-row)*idx[1],   $
         col*idx[0],     (rows-row+1)*idx[1]] $
       +                                      $
        [margins[0], margins[1],              $
         margins[0], margins[1]]
  
    ; back to normalized coords
    pos[0] = pos[0]/!d.x_vsize
    pos[2] = pos[2]/!d.x_vsize
    pos[1] = pos[1]/!d.y_vsize
    pos[3] = pos[3]/!d.y_vsize

    ; add gaps
    pos[0] = pos[0] + xgap
    pos[2] = pos[2] - xgap

    pos[1] = pos[1] + ygap
    pos[3] = pos[3] - ygap

    ;
    ; Finally set the system variables; user shouldn't change them.
    ;
    
    !p.position = pos
    onbottom = (row eq rows) or (rows eq 1)
    onleft = (col eq 1) or (cols eq 1)
    IF keyword_set(doxaxis) THEN onbottom=1
    IF keyword_set(doyaxis) THEN onleft=1
    if onbottom then begin
        !x.tickname = xtickname 
    endif else begin
        !x.tickname = replicate(' ',30)
    endelse
    if onleft then !y.tickname = ytickname else !y.tickname = replicate(' ',30)
    if onbottom then !x.tickformat = xtickformat else !x.tickformat = ''
    if onleft then !y.tickformat = ytickformat else !y.tickformat = ''
    if keyword_set(verbose) then begin
        coords = '['+string(pos,form='(3(f4.2,","),f4.2)')+']'
        plotno = 'Setup for plot ['+strtrim(col,2)+','+strtrim(row,2)+'] of ' $
            +strtrim(cols,2)+'x'+strtrim(rows,2)
        message,/inform,plotno+' at '+coords
    endif



    ; Add titles to overall axes

    ; area covered by entire plot field in device coords
    allpos = $
        [0,                       0,      cols*idx[0], rows*idx[1]] +   $
        [margins[0],     margins[1],        margins[0], margins[1]]
    ;; back to normalized coords
    allpos[0] = allpos[0]/!d.x_vsize
    allpos[2] = allpos[2]/!d.x_vsize
    allpos[1] = allpos[1]/!d.y_vsize
    allpos[3] = allpos[3]/!d.y_vsize

    xCharSizeNorm = float(!d.x_ch_size) / float(!d.x_size)
    yCharSizeNorm = float(!d.y_ch_size) / float(!d.y_size)

    ; top title
    if n_elements(mTitle) ne 0 then begin
        if n_elements(mTitSize) eq 0 then mTitSize = 1.0
        if n_elements(mTitOffset) eq 0 then mTitOffset = 0.0

        ; align middle of region in x
        xpos = (allpos[2] - allpos[0])/2.0 + nmargins[0]
        ; align relative to the top.  Default is right there plus 
        ; one character size.
        ypos = allpos[3] + (mTitOffset+1.0)*yCharSizeNorm

        ; correct for gaps
        ypos = ypos - ygap

        xyouts, $
            xpos, $
            ypos, $
            mTitle, $
            /normal, $
            align = 0.5, $
            charsize = 1.25 * mTitSize
    endif

    ; x title
    if n_elements(mxTitle) ne 0 then begin
        if n_elements(mxTitSize) eq 0 then mxTitSize = 1.0
        if n_elements(mxTitOffset) eq 0 then mxTitOffset = 0.0

        ; align middle of region in x
        xpos = (allpos[2] - allpos[0])/2.0 + nmargins[0]

        ; align middle of region in x
        ypos = allpos[1] - (mxTitOffset+3.0)*yCharSizeNorm

        ; correct for gaps
        ypos = ypos + ygap
        xyouts, $
            xpos, $
            ypos, $
            mxTitle, $
            /normal, $
            align = 0.5, $
            charsize = mxTitSize
    endif



    ; y title
    if n_elements(myTitle) ne 0 then begin
        if n_elements(myTitSize) eq 0 then myTitSize = 1.0
        if n_elements(myTitOffset) eq 0 then myTitOffset = 0.0

        ; align relative to the left side.  Default is right there plus 
        ; one character size.
        xpos = allpos[0] - (myTitOffset+6.0)*xCharSizeNorm
        ;xpos = allpos[0] - (myTitOffset+4.0)*xCharSizeNorm

        ; align middle of region in x
        ypos = (allpos[3] - allpos[1])/2.0 + nmargins[1]


        ; correct for gaps
        xpos = xpos + xgap

        xyouts, $
            xpos, $
            ypos, $
            myTitle, $
            /normal, $
            align = 0.5, $
            orientation = 90.0, $
            charsize = myTitSize
    endif


return
end