Save Multiple Images

[avn3r]

Hello

First of all thanks for the library. It has everything I could ask for and more and the closest thing to creating tradingview style graphs in python with little code.

However, I have one major hurdle. I want to use this library for Data Collection. Be able to save and store lots of images of this graph. I look at the example provided of using screenshots and the callback to save an image but that only works for a specific plot being shown. I want to be able to loop and over ranges. For example, if I select Apple stock and provide at day frequency. I want to save a plot of day 1 to 10 10-20, etc. But I want to do this while looping over the df so I don't have to run the script hit escape change value manually. I need to automate this since I'm collecting lots of images.

Can you point me in the right direction?
I tried something like this without success:

def save():
    global filename
    fplt.screenshot(open(f'{filename}.png', 'wb'))

for i in range(5):
    filename = str(i)
    fplt.timer_callback(save, .5, single_shot=True)  # wait some until we're rendered
    fplt.show()

[highfestiva]

You could use ax.vb.pan_x(percent=+90) to access the "view box" (a pyqtgraph construct) to move 90% of the display width to right. Out of curiosity, what are you going to use these images for?

[highfestiva]

You're a ton better off using the raw data instead of the images. However I don't think it's possible without .show(), but that shouldn't be a major problem? You can load 500k candles per round, then pan through them in zoomed-in level, then load the next 500k and update the plot, pan_x(), etc, etc.

[highfestiva]

To clarify:

1. Load and show().
2. pan_x(steps=-1e10) to far left.
3. Take screenshot().
4. pan_x(percent=+90)
5. If not at same position: goto 2.
6. Load if necessary.
7. Update plots with new data or break.
8. Goto 2.