Get Y value in line chart using cubic lines - swift

I am using the Charts library in an iOS application. The required chart I am implementing, displays realtime values fed from a hardware peripheral. I already implemented adding new entries and scrolling to the latest value, so the chart appears to be updating constantly (sort of flowing to the left from the right side of the screen).
Now I need to draw a circle on the right side of the graph, but for that I would need to receive the Y value for the currently visible X. This is easy to get for the points in the DataSet, but I can't find a way to get Y value for the interpolated points between the DataSet values.
Here is what the graph looks like:

Related

Vertical synchronized bar on multiple plots, following user cursor

I'm trying to create an app for data analysis.
I have multiple channels of acquisition of the same length, including a time vector.
Vectors as therefore synchronized (same index value corrispond to the same time instant for every array).
I display data on different figures (UIAxes) in my app figure.
To better and more easily use the application I would like the following to happen: each time the user hovers the cursor on any plot a vertical bar at the corrisponding x position of the cursor is displayed, on all the figures. All the figures display the same range of x values.
I also have a scatter figure with points from gps, still with the same length of the other arrays.
On that figure I'd really like to have, instead of the vertical line, a crosshair.
I've found this part of code here but I can't adapt it to App Designer and it's also pretty old.
Any kind of help is very welcome.
EDIT: Matlab Version 2020b

pie chart but in another shape

I just wanna ask if it is possible to make a pie chart but in another shape.
An example would be say there were two candidates who ran for governor in a state. I would want to show the results in a chart. I want the shape of the chart to resemble the shape of the geographical location of the state.
I did some digging and this is the only one that showed up which may help me(but not really) https://forums.adobe.com/thread/988130
As your adobe thread implies there are (at least) three issues to consider:
1) you want to show the votes each candidate received as a portion of the area of the state. If your state is nearly square, you could overlay a grid and assign each candidate a number of grid cells according to the votes they received. If the grid cells are county or precinct outlines that works even better, but this isn't a pie chart because a pie chart uses a polar coordinate system.
2) if you really must have a pie chart which is polar, consider that the average viewer may not be able to visually integrate the areas to get meaningful results. Further you will have to integrate the area swept out by the sectors of the pie like a radar screen, and this contour integration is made more difficult by the fact that you must do it numerically. This means you must sample the boundary distance as a function of angular displacement from some center of gravity you have chosen, like the state capitol. But depending on the location of the state capitol, your visual could become even more distorted. Idaho comes to mind.
3) a good compromise might be just to overlay a pie chart on top of a silhouette or map outline of the state with appropriate drop shadows and emphasis to make the pie chart pop as well as the state outline. it would certainly be much quicker as well as much more readable.

Cognos Chart with "No Data Available" although list shows data

I am completely new to Cognos, so sorry if I don't state some necessary information. I can't go into specifics about my chart, but here is the background:
I have a SQL code running into my Query
My chart and list use the same Query and have the exact same fields
My chart is a basic line graph
When I change my aggregate function to total for my y-axis, then I can see the data points
I do not want to use an aggregate function (I need to see all the points for my x and y-axis)
My x-axis is only one object, but it has multiple y-axis values within a year (which is my series). Ex:product-cost-year list,
where my product is the x-axis, cost is the y-axis, and series is year.
How can I get my chart to appear with all my data points? Eventually, I would like to add an upper and lower confidence interval to this chart.
One way to solve this issue is to create another column that simply counts the number of products (1,2,3,...9). We will call this column count. Keep all your fields the same (product for x-axis, cost for y-axis, and year for series). You will want to add count underneath product on the x-axis. You should see your mouse pointer turn to a horizontal line and it will place it under and to the right of product. Make sure not to place it just to the right of product.

Stop Android Graph View from rounding the x-axis

I'm using graph view in my project and got it working just fine. However I don't like the x-axis values. The values I'm passing are 0,0.5,1,1.5,2,2.5...all the way to 23.5. I would like the graph to show every x-axis value on the grid and not rounded values of 0,3.4,6.9,10.3, 13.7 etc. Is there a way to force it to not round and use the x values provided?
the labels are have fix positions and shows the exact value at this point. It seems, that you want to have the another count of labels or other positions. In the current GraphView version you can set set count of labels. When you configure it in the correct way, you should see labels in 0.5-steps.
Have a look at GraphViewStyle#setNumHorizontalLabels

real time plotting on iPhone using core plot?

I want to use core-plot for drawing line graph dynamically. data won't come at a time, we will be receiving point by point dynamically.
Is it possible to draw the chart dynamically using core-plot i.e drawing point by point as on when we receive the (x,y) point?
Please help me, Thanks.
Yes, you can do this reasonably easily. For each received data point, append it to an array of values to display. As these data points come in, call -reloadData on the Core Plot graph (or just the particular plot) to redraw the graph, passing in the array you just added a value to in response to the -numbersForPlot:field:recordIndexRange: delegate method.
If you need to adjust the plot range to track your data points (for a moving ticker), recalculate the new CPPlotRange for the X axis and set the plot space's xRange property to that.
Use the CPTestApp-iPhone, AAPLot, or StockPlot examples as templates for how to set up the line chart overall, and modify from that starting point.
I do something similar to this on the Mac in a scientific application:
(source: sunsetlakesoftware.com)
Sounds like you could make use of a demo project I put together and wrote about here (not core plot related though).
It draws a EKG graph but should easily be modified to use another input than the repeated "heart beat"...See line 320 in EAGLView.m where the indata is entered into the array.