cross_sections.mws About this worksheet Author and Date Content, Purpose and Use Updates and log of modifications. Working with "pure functions" Define a function of 2 variables and plot it Contours and level curves Cross-sections parallel to xz plane Cross-sections parallel to yz plane Radial cross-sections Circular cross-sections Working with "expressions" Define a expression depending on 2 variables and plot it Contours and level curves Cross-sections parallel to xz plane Cross-sections parallel to yz plane Radial cross-sections Circular cross-sections