Graph Builder: Linear Y axis appears to be incorrect

[#1]

Hello,

I am fairly new to JMP scripting and having a weird issue in the Graph Builder. I'm just trying to graph this data on linear X and Y axes. The average of the data (I can't post it, but it is fairly noisy; I am using the smoother for this reason) is 0.06 GPM (calculated using the Mean function further up in the script), but the average of the line on the graph is closer to 0.01 GPM, and the line never even approaches 0.06 GPM. I don't think the noise in the data is enough to cause this much of a disconnect.

This is happening across a range of scripts that do similar things; in cases where the range of flow rates is higher, the y-axis labels even appear nonlinear, with varying distances between tick marks (but not quite exponential or power-based). An example of this kind of scale, and the y-axis settings, are attached. 

Here is my graphing script:

build_graph = dt << Graph Builder(
Show Control Panel( 0 ),
Automatic Recalc( 0 ),
Variables( X( :Timestamp ), Y( :flow rate ) ),
Elements( Smoother( X, Y, Legend( 5 ) ) ),
SendToReport(
Dispatch(
{},
"Timestamp",
ScaleBox,
{Format( "m/y", 7 ), Min( 3611779200 ), Max( 3613248000 ),
Interval( "Week" ), Inc( 0.142857142857143 ), Minor Ticks( 0 )}
),
Dispatch(
{},
"flow rate",
ScaleBox,
{Min( -0.5 ), Max( 153.5 ), Inc( 10 ), Minor Ticks( 0 ),
Show Major Grid( 1 ), Show Minor Grid( 1 )}
)
)
)

I'm running JMP 11.1.1. I've searched these forums and the internet pretty thoroughly and haven't found anyone else having the same problem. I would prefer a scripting answer to the problem, but am happy to troubleshoot however is easiest.

Thank you in advance for your help!

Axis settingsWonky axis

[#2]

Hi Brocolli Liker,

It is difficult to troubleshoot without having an example of the data. Can you send a data set that represents your real data? Also, what is the Data Type and Modeling type for each column used in Graph Builder?

Chris

[#3 · Accepted solution]

It appears that your Y column (Flow Rate) has a categorical modeling type (either ordinal or nominal) and is therefore getting a categorical axis where your actual values are mapped to  a categorical scale.

Modeling types

It should be pretty easy to fix by making sure that your Flow Rate column is set to the Continuous modeling type. If you can't change it to Continous it means that the column is also set to the wrong data type. It should be numeric, not character.

Column Info dialog

[#4]

That fixed it! Thank you so much - you made my life SO MUCH EASIER.

All the best,

Rachel