Scale factor

[simply]

Hi David,
i have a 3d graph that had a scale factor 1:1:1/2, i was sure that it's the default scale, but when i read the user manual about ContourScales i see that the default is 1:1:1???

when i use the NumTicks command the factor scale become 1:1:1, I can't understand why???

i got other problems with the Numticks command, in some cases (i never got this before), the axis limit change and have values greater than needed. And I'm obliger to use TickInterval to correct this.
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[simply]

Hi David,
when i use the NumTicks command the scale become 1:1:1, I can't understand why???

when i use[NumTicks(1," & DivAffichX& & "," & DivAffichY& & ",)] without specifyng a value for Z the factor scale is 1:1:1/2, and every time i change the value of Z the factor scale changes.
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[DPlotAdmin]

Take a look at Options>General. Most likely you have "Always auto-adjust scale factors on 3D plots" checked. If you do, then DPlot will set the scale factor such that the X and Y extents are roughly square when viewed in 2D, and the height of the Z axis is roughly 1/2 the X/Y extents.

Also, if you have that box checked then the scale factors will be adjusted any time you do just about anything on the Extents/Intervals/Size dialog.

The short version is - if you don't want DPlot manipulating the scale factors then uncheck that box.

i got other problems with the Numticks command, in some cases (i never got this before), the axis limit change and have values greater than needed. And I'm obliger to use TickInterval to correct this.

If you're using either of the calendar date number formats on either the X or Y axes, I made a few changes in version 2.1.6 to do a better job with the grid interval - for example it wasn't previously possible to have grid lines at non-constant spacings like 1 month.

If that doesn't explain your problem then please save your graph as a DPlot file and send it to me, along with an explanation of what extents you want and what you do that DPlot isn't handling the way you expect.

[simply]

Take a look at Options>General. Most likely you have "Always auto-adjust scale factors on 3D plots" checked. If you do, then DPlot will set the scale factor such that the X and Y extents are roughly square when viewed in 2D, and the height of the Z axis is roughly 1/2 the X/Y extents.

Also, if you have that box checked then the scale factors will be adjusted any time you do just about anything on the Extents/Intervals/Size dialog.

The short version is - if you don't want DPlot manipulating the scale factors then uncheck that box.

"Always auto-adjust scale factors on 3D plots" is checked, and i suppose that it's by default checked???

what i need, is to always have the factor 1:1:1/2 even when i use numticks or Manualscale. in general i use Numticks(1,6,6,6).

i got other problems with the Numticks command, in some cases (i never got this before), the axis limit change and have values greater than needed. And I'm obliger to use TickInterval to correct this.

If you're using either of the calendar date number formats on either the X or Y axes, I made a few changes in version 2.1.6 to do a better job with the grid interval - for example it wasn't previously possible to have grid lines at non-constant spacings like 1 month.

If that doesn't explain your problem then please save your graph as a DPlot file and send it to me, along with an explanation of what extents you want and what you do that DPlot isn't handling the way you expect.

i'll send you a graph.
________

[DPlotAdmin]

"Always auto-adjust scale factors on 3D plots" is checked, and i suppose that it's by default checked???

No, whatever setting was in effect the last time you shut down DPlot will be in effect the next time it runs. If you want to ensure that that setting is unchecked, use [GeneralOptions(8,0)].

i'll send you a graph.

Received, thanks. DPlot could definitely do a better job with this. There may be a roundoff error in there that is causing it to prefer an interval of 0.25 rather than 0.2 - whatever the case this will be improved in the next release.

[DPlotAdmin]

The problem you found has been in DPlot for a while. You most likely didn't notice it before because you haven't used that combination of extents and number of tick marks.

Neither 0.6 nor 0.2 (the logical choice for interval) can be expressed exactly using floating point numbers, and though DPlot initially picks 0.2 as the interval, it then botches up an attempt to check whether the lower limit (0.6) is a multiple of 0.2. It finds that it isn't, so tries the next tick mark interval (0.25).

This is fixed in today's update. I'll be sending out update notices tonight. In the meantime you can get the latest version with the Check for Updates command on the Help menu.