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I'm performing NDVI calculation on a Planet Scope 4 band image as per Planet's documentation

The following block of code is what I wrote:

Extract band data from original image in working directory

import rasterio import numpy

image_file = "20170430_194027_0c82_3B_AnalyticMS"

with rasterio.open(image_file) as src:    band_red = src.read(3)

with rasterio.open(image_file) as src:    band_nir = src.read(4)

from xml.dom import minidom

xmldoc = minidom.parse("20170430_194027_0c82_3B_AnalyticMS_metadata") nodes = xmldoc.getElementsByTagName("ps:bandSpecificMetadata")

Extract TOA correction coefficients from metadata file in directory

TOA_coeffs = {} for node in nodes:    bn = node.getElementsByTagName("ps:bandNumber")[0].firstChild.data    if bn in ['1', '2', '3', '4']:
       i = int(bn)
       value = node.getElementsByTagName("ps:ReflectanceCoefficient")[0].firstChild.data
       TOA_coeffs[1] = float(value)

Calculate NDVI and save file

band_red = band_red * TOA_coeffs[3] band_nir = band_nir * TOA_coeffs[4]

numpy.seterr(divide = 'ignore', invalid = 'ignore')

NDVI = (band_nir.astype(float) - band_red.astype(float))/(band_nir + band_red) numpy.nanmin(NDVI), numpy.nanmax(NDVI)

kwargs = src.meta kwargs.update(dtype=rasterio.float32, 
             count = 1)

with rasterio.open('ndvi.tif', 'W', **kwargs) as dst:    dst.write_band(1, NDVI.astype(rasterio.float32))

Add symbology and plot color bar

import matplotlib.pyplot as plt import matplotlib.colors as colors

class MidpointNormalize(colors.Normalize):    def __init__(self, vmin=None, vmax=None, midpoint=None, clip=False):
       self.midpoint = midpoint
       colors.Normalize.__init__(self, vmin, vmax, clip)
           def __call__(self, value, clip=None):
       x, y = [self.vmin, self.midpoint, self.vmax], [0, 0.5, 1]
       return numpy.ma.masked_array(numpy.interp(value, x, y), >numpy.isnan(value))
    min = numpy.nanmin(NDVI) min = numpy.nanmax(NDVI) mid = 0.1

fig = plt.figure(figsize= (20,10)) ax = fig.add_subplot(111)

cmap = plt.cm.RdYlGn

cax = ax.imshow(NDVI, cmap=cmap, clim=(min,max),
>norm=MidpointNormalize(midpoint=mid, vmin=min, vmax=max))

ax.axis('off') ax.set_title('NDVI_test', fontsize= 18, fontweight='bold')

cbar = fig.colorbar(cax, orientation= 'horizontal', shrink=0.65)

fig.savefig("output/NDVI_test.png", dpi=200, bbox_inches='tight',
>pad_inches=0.7)

plt.show()

Plot histogram for NDVI pixel value distribution

fig2 = plt.figure(figsize=(10,10)) ax = fig2.add_subplot(111)

plt.title("NDVI Histogram", fontsize=18, fontweight='bold') plt.xlabel("NDVI values", fontsize=14) plt.ylabel("# pixels", fontsize=14)

x = NDVI[~numpy.isnan(NDVI)] numBins = 20 ax.hist(x,numBins,color='green',alpha=0.8)

fig2.savefig("output/ndvi-histogram.png", dpi=200, bbox_inches='tight', >pad_inches=0.7)

plt.show()

Alas, the execution of the script is cut short at the beginning of the code:

File "C:/Users/David/Desktop/ArcGIS files/Planet Labs/2017.6_Luis_Bedin_Bolivia/planet_order_58311/20170430_194027_0c82/TOA_correction_NDVI.py", line 8, in <module>
    import rasterio
ModuleNotFoundError: No module named 'rasterio'

So I decide to install rasterio, that should solve the problem:

C:\Users\David\Desktop\ArcGIS files\Planet Labs\2017.6_Luis_Bedin_Bolivia\planet_order_58311\20170430_194027_0c82>pip install rasterio
Collecting rasterio
  Using cached rasterio-0.36.0.tar.gz
Requirement already satisfied: affine in c:\users\david\anaconda3\lib\site-packages (from rasterio)
Requirement already satisfied: cligj in c:\users\david\anaconda3\lib\site-packages (from rasterio)
Requirement already satisfied: numpy in c:\users\david\anaconda3\lib\site-packages (from rasterio)
Requirement already satisfied: snuggs in c:\users\david\anaconda3\lib\site-packages (from rasterio)
Requirement already satisfied: click-plugins in c:\users\david\anaconda3\lib\site-packages (from rasterio)

What I interpret from this is that rasterio is already installed. How can this be if the Python console tells me there's no module named rasterio. The output from the console also says Microsoft Visual C++ is required. Upon further research I find this user's solution. I tried it but the console also tells me that rasterio is already installed:

(envpythonfs) C:\Users\David\Desktop\ArcGIS files\Planet Labs\2017.6_Luis_Bedin_Bolivia\planet_order_58311\20170430_194027_0c82>conda install rasterio gdal
Fetching package metadata .............
Solving package specifications: .

# All requested packages already installed.
# packages in environment at C:\Users\David\Anaconda3\envs\envpythonfs:
#

I'm creating the script using Spyder 3.1.2 with Python 3.6 on a Windows 10 64-bit machine.

  • You may want to try asking on a different SE site that gets more Windows+Python users, since this isn't specifically a GIS question. – bosth Jul 27 '17 at 20:16
1

When you ran pip install rasterio above, it shows using a cached copy, which means it did have to install it. The "Requirement already satisfied" messages are shown for the other dependencies. I would assume that the script should work if you try it again.

0

Download anaconda from https://www.anaconda.com/download/ and use Anconda CLI to run your python file. It's very easy to install packages in Anaconda.

rasterio can be installed by:

conda install -c https://conda.anaconda.org/ioos rasterio

It works fine for me. Give it a try

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