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<h1class="fqn"><spanclass="in-band">Module <ahref="../../../index.html">halo2_gadgets</a>::<wbr><ahref="../../index.html">ecc</a>::<wbr><ahref="../index.html">chip</a>::<wbr><aclass="mod"href="#">constants</a><buttonid="copy-path"onclick="copy_path(this)"title="Copy item path to clipboard"><imgsrc="../../../../clipboard.svg"width="19"height="18"alt="Copy item path"></button></span></h1><spanclass="out-of-band"><aclass="srclink"href="../../../../src/halo2_gadgets/ecc/chip/constants.rs.html#1-282">source</a> · <aid="toggle-all-docs"href="javascript:void(0)"title="collapse all docs">[<spanclass="inner">−</span>]</a></span></div><detailsclass="rustdoc-toggle top-doc"open><summaryclass="hideme"><span>Expand description</span></summary><divclass="docblock"><p>Constants required for the ECC chip.</p>
</div></div><divclass="item-row"><divclass="item-left module-item"><aclass="constant"href="constant.NUM_WINDOWS.html"title="halo2_gadgets::ecc::chip::constants::NUM_WINDOWS constant">NUM_WINDOWS</a></div><divclass="item-right docblock-short"><p>Number of windows for a full-width scalar</p>
</div></div><divclass="item-row"><divclass="item-left module-item"><aclass="constant"href="constant.NUM_WINDOWS_SHORT.html"title="halo2_gadgets::ecc::chip::constants::NUM_WINDOWS_SHORT constant">NUM_WINDOWS_SHORT</a></div><divclass="item-right docblock-short"><p>Number of windows for a short signed scalar</p>
<divclass="item-table"><divclass="item-row"><divclass="item-left module-item"><aclass="fn"href="fn.compute_lagrange_coeffs.html"title="halo2_gadgets::ecc::chip::constants::compute_lagrange_coeffs fn">compute_lagrange_coeffs</a></div><divclass="item-right docblock-short"><p>For each window, we interpolate the $x$-coordinate.
Here, we pre-compute and store the coefficients of the interpolation polynomial.</p>
</div></div><divclass="item-row"><divclass="item-left module-item"><aclass="fn"href="fn.find_zs_and_us.html"title="halo2_gadgets::ecc::chip::constants::find_zs_and_us fn">find_zs_and_us</a></div><divclass="item-right docblock-short"><p>For each window, $z$ is a field element such that for each point $(x, y)$ in the window:</p>
</div></div><divclass="item-row"><divclass="item-left module-item"><aclass="fn"href="fn.test_zs_and_us.html"title="halo2_gadgets::ecc::chip::constants::test_zs_and_us fn">test_zs_and_us</a><spanclass="stab portability"title="Available on crate feature `test-dependencies` only"><code>test-dependencies</code></span></div><divclass="item-right docblock-short"><p>Test that the z-values and u-values satisfy the conditions: