Fourier Transform Infrared Spectroscopy (FTIR) dataset

The following FTIR dataset, was obtained as a JCAMP-DX file, and subsequently converted to the CSD model file-format. The data structure of the FTIR dataset follows,

import matplotlib.pyplot as plt

import csdmpy as cp

filename = "https://www.ssnmr.org/sites/default/files/CSDM/ir/caffeine_base64.csdf"
FTIR_data = cp.load(filename)
print(FTIR_data.data_structure)

{
  "csdm": {
    "version": "1.0",
    "read_only": true,
    "timestamp": "2019-07-01T21:03:42Z",
    "description": "An IR spectrum of caffeine.",
    "dimensions": [
      {
        "type": "linear",
        "count": 1842,
        "increment": "1.930548614883216 cm^-1",
        "coordinates_offset": "449.41 cm^-1",
        "quantity_name": "wavenumber",
        "reciprocal": {
          "quantity_name": "length"
        }
      }
    ],
    "dependent_variables": [
      {
        "type": "internal",
        "name": "Caffeine",
        "numeric_type": "float32",
        "quantity_type": "scalar",
        "component_labels": [
          "Transmittance"
        ],
        "components": [
          [
            "99.31053, 99.08212, ..., 100.22944, 100.22944"
          ]
        ]
      }
    ]
  }
}

and the corresponding plot.

plt.figure(figsize=(5, 3.5))
ax = plt.subplot(projection="csdm")
ax.plot(FTIR_data)
ax.invert_xaxis()
plt.tight_layout()
plt.show()

Because, FTIR spectrum is conventionally displayed on a reverse axis, an optional reverse_axis argument is provided to the plot() method. Its value is an order list of boolean, corresponding to the order of the dimensions.