Drawing a line graph with dynamic plotting in ios - ios

I am going to develop an app which takes current and voltage as input values. I need to display certain values which are generated infinite times on applying certain calculations on those inputs in a graph. I have searched many web pages but I am not able to understand the real facts. Is there any way to plot line graph with plotting of points dynamically in iOS?

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plotly.js "pseudo" histogram for time-series data?

I am trying to figure out how to create this overlaid plot of time-series data, where one of the series should "look" like a histogram.
The problem is I could not figure out how to combine/overlay a histogram with time series data and line/scatter plot and get the histogram xbins to work with the date time data, etc.
So I was also trying to use a bar chart, and create a "pseudo histogram" by removing the gaps between bars, adding outlines, and so forth but that seems fruitless as I don't see a way to control all the borders/lines to that level of control.
The result I am looking for is roughly like so;
Which to me looks like the best match for a plot type should be a histogram, but again I could not figure out how to make that work overlaid with the same x axis as the line/scatter time-series data.
Can anyone offer ideas or point me to an example that might help me understand how to do this ?
I guess I also need to figure out how to align the y-axis scales of the two series also, but that I expect is a different topic...
I am specifically using plotly.js / Javascript

Find top n places that close to a route

I have lots of places data(tourist attractions) stored in database. Every place has coordination info, such as latitude and longitude. When I randomly choose a route (for example: from somewhere in New York to somewhere in Boston), how can I find the 10 closest places along the route? I guess it's relative to geography algorithms. I'm trying to find a way to minimize the total calculation time and save cell phone battery. Thank you for any suggestions!
One way would be:
Consider the map to be a grid eg of 1km x1km boxes
plot the route and see which of these grid boxes it enters.
for each box, find the places/landmarks in the box which is not computationally expensive if you search your database my min/max longitude/latidtude position where the grid box starts/ends
To show the top N from these, you can calculate the shortest distance for these subset of places rather than the whole dataset.

Map performance with polylines containing many thousands of points

The application we are developing needs to show historic movement data consisting of hundreds of thousands of points. Performance degrades as the number of points per polyline increases, or the number of polylines increases. What is the best way of improving performance in this instance?
Perhaps somehow baking the polylines into maptiles and including these as additional layers? We are currently targeting iOS9+, using ios-v3.2.0.

Multiple Plotspaces or shifted axes/plots

I'm looking to incorporate 4 real time scatter-plots into a graph and it has been requested that they be separated (at least in pairs) to make it easier to pick out signals. Would it be less resource intensive to have multiple plotspaces on my graph, or shift a new set of axes and plots on the same plotspace? Is this still the case if I add 2-4 more scatter-plots (for 6-8 total)?
FYI, I'm currently using CorePlot 1.6 (haven't had time to make the jump to 2.0).
If all of the plots are in the same graph, use multiple plot spaces. A plot space just defines a coordinate mapping between the data and the screen so it does't use any video memory or other system resources (just a small amount of memory for the plot space object itself). Each plot and axis are CALayer objects, so those will be the primary drivers of resource usage.

Using a straight line in ScatterPlot Coreplot iOS

I'm trying to draw a graph using the coreplot library. I'm looking for a way to change the dataLineStyle of the graph so that all the dots will be connected in a straight line, without any playful turns. If needed, I can provide more information.
Is there any way to achieve this?
[EDIT]
I have included a picture to better understand what I'm talking about. I would not like the Graph Line to go above or under the data points.
Regression lines aren't built into Core Plot. You can use one scatterplot to draw the data points with just plot symbols and no data line. Use a second scatter plot to draw the regression line. It only needs two data points, one for each end of the line. You'll have to compute the regression coefficients yourself.
The lines connecting the data points are controlled by the interpolation property. The default is CPTScatterPlotInterpolationLinear which is what you want.

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