Ran Xue

倾斜色标字体

res@lbLabelAngleF    =    45                 ; angle labels

只画指定值的等值线

res3@cnLevelSelectionMode = "ExplicitLevels"
res3@cnLevels = (/2/)
res3@cnMonoLineThickness = False
res3@cnLineThicknesses = (/2/)

ncl色标常用设置

res@lbOrientation="Vertical" ;竖直放置
res@lbBoxEndCapStyle      = "TriangleBothEnds"  ；两段为三角形
res@tmYRMode             = "Automatic"          ; turn off special labels on right axis
res@@lbLabelsOn             = True
res@lbLabelFontHeightF      = 0.02     ;set the size of label bar words
res@pmLabelBarHeightF      = 0.15     
res@tmYROn=False  ;关闭刻度
;res@tmYRBorderOn =False ;关闭线
res@tmYRLabelsOn  =False


resp@pmLabelBarParallelPosF     = 0.17  ;色标左右移动
;resp@pmLabelBarOrthogonalPosF   = -0.1  ;色标上下移动
resp@pmLabelBarWidthF         = 0.5   ;长度
resp@pmLabelBarHeightF        = 0.07  ;宽度
; resp@lbLabelFontHeightF       = 0.015

坐标轴字体大小设置

res@tmXBLabelFontHeightF    = 0.02     ;set the size of x-Axis words
res@tmYLLabelFontHeightF    = 0.02    ;set the size of y-Axis words
注意极地投影经纬度的字体大小设置为：
res1@gsnPolarLabelFontHeightF= .04

res_vec@tmYRMode             = "Automatic"          ; turn off special labels on right axis
res_vec@tiYAxisString=""
res@tmYRLabelsOn = False
res@gsnPresHgtHeightLabelOn = False

colorbar设置

;res1@cnLevelSelectionMode= "ExplicitLevels"
;res1@cnLevels = (/-12,-10,-8,-6,-4,-2,0,2,4/); 值
;res1@cnFillColors =     (/2,4,5,6,7,8,9,11,15,17,19/) ;颜色设置


res1@cnLevelSelectionMode = "ManualLevels"       ; manually select levels
res1@cnLevelSpacingF      = 0.5              ; contour spacing
res1@cnMinLevelValF       = -4              ; min level
res1@cnMaxLevelValF       = 4             ; max level

等值线标签

res1@cnInfoLabelOn               = False  

等值线数值标签

res1@cnLineLabelsOn =False
;等值线数值标签
res3@cnLineLabelsOn =   True
res3@cnLineLabelAngleF=0 ;标签角度
res3@cnLineLabelBackgroundColor ="white";标签边框内部颜色
res3@cnLineLabelDensityF=0.5 ;修改等值线上标签数目的相对密度
res3@cnLineLabelPerimOn=True ;添加边框
res3@cnLineLabelPerimColor="white" ;边框颜色
res3@cnLineLabelPlacementMode="Computed" ;绘制标签的算法
res3@cnLineLabelFontHeightF       =0.025

图片之间间隔

resp@gsnPanelYWhiteSpacePercent=3

数组维度转换

z_D1 =f_z->$varnameh$(D,{levP},{lat1:lat2},:)
z_D  = reshape(z_D1,(/1,dsizes(0),dsizes(1)/))
printVarSummary(z_D)

创建文件若存在则删除

outFx="/raid63/xran/Research_ERA5/why/TN_Fulx_data/TN2001-Fx"+fmon+""+fyear+".monthly.nc"
if (isfilepresent(outFx)) then
    system("rm -f "+outFx)
end if

提取每一年对应的月

ctime = time(fstep:lstep:12) ;每年对应的月
nctime = dimsizes(ctime)     
zvar = zvarorg(fstep:lstep:12,:,:,:)

组图一张图时不居中

resp@gsnPanelCenter = False

时间提取

yyyymm = cd_calendar(eof_ts&time,-2)/100 

xy轴型图片添加网格

;res1@tmXMajorGrid= True;, Turns on the grid in the x-direction.
;res1@tmXMajorGridThicknessF      = 1.0           ; 2.0 is default
;res1@tmXMajorGridLineDashPattern = 2             ; select short dash lines

;res1@tmYMajorGrid                = True          ; implement y grid
;res1@tmYMajorGridThicknessF      = 1.0           ; 2.0 is default
;res1@tmYMajorGridLineDashPattern = 2             ; select short dash lines

计算月平均值

calculate_monthly_values
具体使用见ncl官网
读取一年的每日值（时间，水平，纬度，经度）并计算月平均值。该值为类型为“short”，带有scale_factor和“加法偏移量”。n基准是指“时间”维度（n基准=0）。

f = addfile("air.day.2008.nc","r")
x = short2flt(f->air)
printVarSummary(x)
opt = True
opt@nval_crit = 12   ; require at least 12 values for the "avg" is calculated.
xMon = calculate_monthly_values (x, "avg", 0,opt)
printVarSummary(xMon)
输出如下所示：
Variable: xMon
Type: float

Number of Dimensions: 4
Dimensions and sizes:   [time | 12] x [level | 17] x [lat | 73] x [lon | 144]
Coordinates: 
time: [17593032..17601072]
level: [1000..10]
lat: [90..-90]
lon: [ 0..357.5]

维度

nlat = dimsizes(lat)
nlon = dimsizes(lon)
nlevel = dimsizes(level)
res_vec@tmYRMode             = "Automatic"          ; turn off special labels on right axis  

将变量输出保存

运行ncl命令时ncl *.ncl >&1.txt将变量输出保存

出图图片旋转

gsnPaperOrientation = ″portrait″（纵向）″landscape″（横向）

°符号

["+youwantlats+"-"+youwantlate+"~S~o~N~N]

提取变量的时间维度

date    = cd_calendar(x&time,-2)        ; yyyymmdd
yrfrac  = yyyymmdd_to_yyyyfrac (date, 0)
delete(yrfrac@long_name)
delete(x@long_name)

pStrt = 19950101      ; 4 years: winter 96-97 MJO gold standard
pLast = 19981231
iStrt = ind(date.eq.pStrt)        ; user specified dates
iLast = ind(date.eq.pLast)
delete(date)

间隔

res1@mpGridLonSpacingF = 90.

;地图上经度与纬度线的间隔
res1@gsnMajorLonSpacing=90
res1@gsnMajorLatSpacing=20

;地图上网格的间隔
res1@mpGridAndLimbOn         = True
res1@mpGridLatSpacingF       = 20
res1@mpGridLonSpacingF       = 90
res1@mpGridLineDashPattern   = 1
res1@mpGridLineColor         ="black"
res1@mpGridLineThicknessF   =0.5

底图地图线的颜色和粗细

res1@mpGeophysicalLineColor = "gray" 
res1@mpGeophysicalLineThicknessF = 0.5; - Changes the thickness of continental outlines.

XY轴刻度线标签

;XY轴的标签不显示
res_vec@tmYLLabelsOn=False
res_vec@tmXBLabelsOn=False
;某一幅图显示，其他不显示数值，但图片大小不一致，控制子图的属性；
res@gsnMaximize= False  
resPanel@gsnMaximize = True  
;调节图片间距
;展板中各子图空白间距过大如何调节？增加空白间隙距离的
resPanel@gsnPanelYWhiteSpacePercent         = 0.5  
resPanel@gsnPanelXWhiteSpacePercent         = 0.2  
;调整各子图的位置减小间隙
resPanel@gsnPanelXF                                         = (/0.1,0.38,0.66,0.1,0.38,0.66/)     ；各个子图的横向位置
resPanel@gsnPanelYF                                         = (/-1,-1,-1,-1,-1,-1/)    ；-1是默认值

子图标号

resPanel@gsnPanelFigureStrings                                      = (/"(a)","(b)","(c)","(d)","(e)","(f)"/)
resPanel@gsnPanelFigureStringsFontHeightF                      = 0.02
resPanel@amJust                                                        = "TopLeft"    ；位置，默认是在右下方
resPanel@gsnPanelFigureStringsPerimOn                    = False          ;去掉方框的边框
resPanel@gsnPanelFigureStringsBackgroundFillColor    =-1                ;方框背景设置为透明

极地投影坐标距离图片

res@gsnPolarLabelDistance=1.08 ;默认为1.04

reverse colormap

cmap = read_colormap_file("precip4_diff_19lev") ; read color data
cmap = cmap(::-1,:)                             ; reverse colormap
res@cnFillPalette        = cmap 

colorbar选择颜色区域

res@gsnSpreadColors=True
res@gsnSpreadColorStart=100
res@gsnSpreadColorEnd=255