{ "cells": [ { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "import numpy as np" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "# Detect overflow with two rasters" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "im1 = np.arange(16*9*1).astype(np.uint8).reshape(16,9,1)\n", "\n", "im2 = im1.copy()\n", "f = np.random.random(im2.shape) < .2\n", "im2[f] += 1" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Detection" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "(im2 > im1).any()" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "old_settings = np.seterr(all='ignore')\n", "np.seterr(all='print')\n", "np.unique(im1 - im2)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "# Detect overflow in a Stack" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "stack = np.arange(16*9*4).astype(np.uint8).reshape(16,9,4)\n", "stack.shape" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "(stack[:,:,1:] > stack[:,:,:-1]).any()" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "np.subtract(stack[:,:,:-1], stack[:,:,1:], dtype=stack.dtype)" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "stack.dtype.str\n", "np.dtype('|i1')" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "t = str(stack.dtype)\n", "np.dtype('int8')" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "t.replace('u', '')" ] }, { "cell_type": "code", "execution_count": null, "metadata": {}, "outputs": [], "source": [ "t.lstrip('u')" ] } ], "metadata": { "kernelspec": { "display_name": "Python 3", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3" } }, "nbformat": 4, "nbformat_minor": 2 }