FAQ
Ferret FAQs
Ferret FAQs
GRAPHICS: Hard Copy - Animations - Custom Labels - Custom Plots - Map projections - X Window
DATA MANAGEMENT: Data Sources - NetCDF - Axes and Data - Shapefiles
We will fill in more answer pages as we have time. Questions without links are on our list to answer. You may expedite the process by letting us know which questions are most important to you or by suggesting new ones.
Happy Ferreting!
Graphics
- getting valid EPS files from Fprint
- CMYK format for postscript files
- controlling the size of GIF or PNG output
- removing the logo from your plots
- colored labels
- colored symbols
- ASCII characters in labels
(How can I make a percent sign in a label?) - changing to another font from ASCII font
(How can I change Ferret fonts or use special PPLUS characters once I've changed to ASCII font?)
- What's the quickest way to get a custom label onto my plot?
- The /NOLABELS qualifier doesn't remove the axis labels!
- Locating a label based on the date on a time axis plot.
- Contour labels (frequency, size, precision, prefix, ...).
- Presentation graphics: bold, large contour labels, etc.
- How can I use the label information that Ferret puts onto plots but modify the location, style, or text of the labels?
- labeling dates along a trackline
- setting plot background color
- laying out multiple plots
- How can I control the colors in FILL and SHADE plots?
- black and white graphics
- colors and patterns
- How can I choose a good color palette for my plot?
- Which of Ferret's color palettes best convey information to color-impaired viewers?
- What palettes will show up well if I photocopy the output, or display it using LCD projectors, Laptop and CRT screens, and color printers?
- How can I create a palette to show out-of-bounds data?
- modifying the shade key
(How can I change the size & position of the color bar?) - modifying the legend (key) for a multi line plot
- Custom legends for line plots
- Specifying positions on your plot: PLOT+ user units versus inches.
- Control over precise layout on hard copy (Fprint controls).
- changing line thickness in PostScript files
(How can I control line thickness when I translate a metafile to a postscript file?) - How to plot scattered symbols and lines over a contour plot (e.g. GO land and including the case of contouring on a time axis)
- How do I control the choice of symbols on multi-line plots?
- How can I make a 2D log (or log-log) plot?
- How can I make a plot in which the vertical axis is split into two scale factors?
- Plots with error bars.
- Wind barbs/stick vectors.
- Can I put an upper limit on vector sizes in Ferret?
- Overlaying bottom bathymetry on a section plot.
- Overlaying scattered symbols on a contour field.
- Overlaying scattered vectors on a contour field.
- Plotting with multiple axis scales.
- How can I overlay symbols on a plot with a time axis?
- How can I overlay a time series on a SHADE or FILL plot?
- How can I draw a second vertical axes on a contour plot?
- How can I plot model output with equal-length months?
- Where can I get detailed coastlines and political borders to overlay on my plots?
- Where can I get detailed topography and bathymetry data?
- How can I fill between two curves?
- How can I contour a mask so that it matches the grid cells?
- How can I outline a mask on a plot with a map projection?
- Is there a way to make a continuous colorbar without lines between the levels?
- How can I improve the text on my plots for publication?
- Can I use Ferret to draw a Taylor Diagram?
Map projections and Curvilinear data
- How do I create map projections with Ferret?
- How can I get the right aspect ratio for a plot when I'm using a map projection and a sub-global region?
- How can I get the right aspect ratio for map projections in viewports?
- How can I put my curvilinear coordinate data in a map projection?
- All I want to do is plot a ship track with a particular map projection.
- How does ferret generate boundaries for the curvilinear (3-argument) shade command?
- How can I create publication-quality map projection plots?
- How can I outline a mask on a plot with a map projection?
- How can I plot a subset of my curvilinear data?
- How can I show the grid on my map projection plots?
Analysis
- Units that result from integration, differentiation, and other transforms
- Averaging/integrating over irregular regions in Ferret.
- How do I create an indefinite integral that integrates "backwards" (towards decreasing values)?
- Determining/setting the filter widths of smoothers.
- Which are the best filters to use for high and low-pass filtering?
- Computing correlations
- Computing least squares, regressions, detrending data
- How can I create a seasonal mask?
- How do I calculate climatologies and climatological anomalies?
- How do I compute a daily climatology for a time series?
- How can I produce a time series of annual averages (or other intervals) from a monthly time series?
- How can I determine the averaging weights when regridding with @AVE?
- What are "grid-changing functions" and how do they handle region information?
- How can I find the LAST occurrence of an event or value
- How can I show the value of my variable at its deepest depth?
- How does Ferret compute averages and integrals on the surface of the surface of the earth?
- How can I call SCAT2GRID functions for my DSG data?
Data Management
- Where can I get detailed coastlines and political borders to overlay on my plots?
- Where can I get detailed topography and bathymetry data?
- Finding OPeNDAP datasets
- How do I make my model write out NetCDF files that are suitable for Ferret?
- How do I tell ferret that NaN means "missing value" in a .cdf file?
- Are there any disadvantages to using reversed coordinates?
- How can I use data as a time series when it exists in multiple files?
- What variable names conflict with reserved keywords?
- I have a NetCDF file that Ferret refuses to read.
- How can I check for the existence of a file or URL?
- Density axis <--> depth axis.
- Working with ungridded (scattered) data.
- Reading ASCII data representing gridded data
- How can I set a missing value over land?
- How do I handle sigma coordinate output in Ferret?
- Models based on curvilinear coordinates.
- How can I plot model output with equal-length months?
- Negative time step values.
- Creating modulo time axes.
- How do I merge a spatially scattered collection of time series or profiles into higher dimensioned grids?
- Is there any way to plot the value of each pixel on the plot?
- I have model output and I want to extract it along a transect which matches an ocean cruise.
- How can I create a time axis from variables containing year, month, day, etc?
- How can I work with ARGO float profile data?
System issues
Error Messages
Other
-
- Memory usage problems.
- How can I run Ferret in genuine batch mode?
- Troubleshooting the FRAME command.
- Controlling Ferret from a Unix script or other program.
- How to speed up large calculations
- What kind of X Windows environment do I need to run Ferret?
- How can I run Ferret without X-Windows?